--- _id: '61523' abstract: - lang: eng text: AbstractMetasurface holography offers a powerful approach for manipulating wavefronts at the nano and micro scale. Extensive research has been conducted to enhance the multiplexing capacity for diverse wavefronts. However, the independence of multiplexed channels is fundamentally restricted in techniques using single‐layer metasurfaces, resulting in unavoidable crosstalk and the need for post‐filtering of the output wavefronts. Here, a universal wavefront multiplexing concept is presented based on non‐injective transformation. By employing joint optimization on two metasurfaces, different channels can be independently designed without any constraints on the output wavefronts. To validate this approach, ultra‐compact orbital angular momentum (OAM) sorters are designed. In these experiments, the output beams from different channels can be independently mapped to 2D positions with high fineness. In another application of wavefront‐multiplexed holography, 10‐channel multiplexing is experimentally achieved with minimal crosstalk and without the need for post‐processing. These results demonstrate the independence between channels enabled by the non‐injective transformation in the method. The precise wavefront control and high multiplexing capacity underscore its potential for scalable wavefront manipulation devices. article_number: e11823 article_type: original author: - first_name: Xiao full_name: Jin, Xiao last_name: Jin - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 citation: ama: Jin X, Zentgraf T. Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation. Advanced Materials. 2026;38. doi:10.1002/adma.202511823 apa: Jin, X., & Zentgraf, T. (2026). Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation. Advanced Materials, 38, Article e11823. https://doi.org/10.1002/adma.202511823 bibtex: '@article{Jin_Zentgraf_2026, title={Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation}, volume={38}, DOI={10.1002/adma.202511823}, number={e11823}, journal={Advanced Materials}, publisher={Wiley}, author={Jin, Xiao and Zentgraf, Thomas}, year={2026} }' chicago: Jin, Xiao, and Thomas Zentgraf. “Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation.” Advanced Materials 38 (2026). https://doi.org/10.1002/adma.202511823. ieee: 'X. Jin and T. Zentgraf, “Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation,” Advanced Materials, vol. 38, Art. no. e11823, 2026, doi: 10.1002/adma.202511823.' mla: Jin, Xiao, and Thomas Zentgraf. “Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation.” Advanced Materials, vol. 38, e11823, Wiley, 2026, doi:10.1002/adma.202511823. short: X. Jin, T. Zentgraf, Advanced Materials 38 (2026). date_created: 2025-10-06T05:42:21Z date_updated: 2026-03-10T08:32:37Z department: - _id: '15' - _id: '230' - _id: '289' - _id: '623' doi: 10.1002/adma.202511823 intvolume: ' 38' language: - iso: eng main_file_link: - open_access: '1' url: https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202511823 oa: '1' project: - _id: '53' name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: TRR 142 - Project Area A - _id: '55' name: TRR 142 - Project Area B - _id: '65' name: 'TRR 142; TP A08: Nichtlineare Kopplung von Zwischenschicht-Exzitonen in van der Waals-Heterostrukturen an plasmonische und dielektrische Nanokavitäten' - _id: '170' name: 'TRR 142; TP B09: Effiziente Erzeugung mit maßgeschneiderter optischer Phaselage der zweiten Harmonischen mittels Quasi-gebundener Zustände in GaAs Metaoberflächen' publication: Advanced Materials publication_identifier: issn: - 0935-9648 - 1521-4095 publication_status: published publisher: Wiley quality_controlled: '1' status: public title: Independent Wavefront Multiplexing with Metasurfaces via Non‐Injective Transformation type: journal_article user_id: '30525' volume: 38 year: '2026' ... --- _id: '58606' author: - first_name: Albert full_name: Mathew, Albert last_name: Mathew - first_name: Rebecca full_name: Aschwanden, Rebecca last_name: Aschwanden - first_name: Aditya full_name: Tripathi, Aditya last_name: Tripathi - first_name: Piyush full_name: Jangid, Piyush last_name: Jangid - first_name: Basudeb full_name: Sain, Basudeb last_name: Sain - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 - first_name: Sergey full_name: Kruk, Sergey last_name: Kruk citation: ama: Mathew A, Aschwanden R, Tripathi A, et al. Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials. Nano Letters. Published online 2025. doi:10.1021/acs.nanolett.4c06188 apa: Mathew, A., Aschwanden, R., Tripathi, A., Jangid, P., Sain, B., Zentgraf, T., & Kruk, S. (2025). Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials. Nano Letters. https://doi.org/10.1021/acs.nanolett.4c06188 bibtex: '@article{Mathew_Aschwanden_Tripathi_Jangid_Sain_Zentgraf_Kruk_2025, title={Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials}, DOI={10.1021/acs.nanolett.4c06188}, journal={Nano Letters}, publisher={American Chemical Society (ACS)}, author={Mathew, Albert and Aschwanden, Rebecca and Tripathi, Aditya and Jangid, Piyush and Sain, Basudeb and Zentgraf, Thomas and Kruk, Sergey}, year={2025} }' chicago: Mathew, Albert, Rebecca Aschwanden, Aditya Tripathi, Piyush Jangid, Basudeb Sain, Thomas Zentgraf, and Sergey Kruk. “Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials.” Nano Letters, 2025. https://doi.org/10.1021/acs.nanolett.4c06188. ieee: 'A. Mathew et al., “Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials,” Nano Letters, 2025, doi: 10.1021/acs.nanolett.4c06188.' mla: Mathew, Albert, et al. “Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials.” Nano Letters, American Chemical Society (ACS), 2025, doi:10.1021/acs.nanolett.4c06188. short: A. Mathew, R. Aschwanden, A. Tripathi, P. Jangid, B. Sain, T. Zentgraf, S. Kruk, Nano Letters (2025). date_created: 2025-02-12T12:54:41Z date_updated: 2025-02-12T13:02:21Z department: - _id: '15' - _id: '230' - _id: '289' - _id: '623' doi: 10.1021/acs.nanolett.4c06188 language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/2501.11920 oa: '1' project: - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '170' grant_number: '231447078' name: 'TRR 142 - B09: TRR 142 - Effiziente Erzeugung mit maßgeschneiderter optischer Phaselage der zweiten Harmonischen mittels Quasi-gebundener Zustände in GaAs Metaoberflächen (B09*)' - _id: '65' grant_number: '231447078' name: 'TRR 142 - A08: TRR 142 - Nichtlineare Kopplung von Zwischenschicht-Exzitonen in van der Waals-Heterostrukturen an plasmonische und dielektrische Nanokavitäten (A08)' publication: Nano Letters publication_identifier: issn: - 1530-6984 - 1530-6992 publication_status: published publisher: American Chemical Society (ACS) status: public title: Nonreciprocal Metasurfaces with Epsilon-Near-Zero Materials type: journal_article user_id: '30525' year: '2025' ... --- _id: '60565' article_number: '104103' author: - first_name: Adriana full_name: Bocchini, Adriana id: '58349' last_name: Bocchini orcid: 0000-0002-2134-3075 - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 citation: ama: Bocchini A, Gerstmann U, Schmidt WG. Microscopic origin of gray tracks in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>KTiOPO</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math>. Physical Review B. 2025;111(10). doi:10.1103/physrevb.111.104103 apa: Bocchini, A., Gerstmann, U., & Schmidt, W. G. (2025). Microscopic origin of gray tracks in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>KTiOPO</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math>. Physical Review B, 111(10), Article 104103. https://doi.org/10.1103/physrevb.111.104103 bibtex: '@article{Bocchini_Gerstmann_Schmidt_2025, title={Microscopic origin of gray tracks in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>KTiOPO</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math>}, volume={111}, DOI={10.1103/physrevb.111.104103}, number={10104103}, journal={Physical Review B}, publisher={American Physical Society (APS)}, author={Bocchini, Adriana and Gerstmann, Uwe and Schmidt, Wolf Gero}, year={2025} }' chicago: Bocchini, Adriana, Uwe Gerstmann, and Wolf Gero Schmidt. “Microscopic Origin of Gray Tracks in <mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML"><mml:Msub><mml:Mi>KTiOPO</Mml:Mi><mml:Mn>4</Mml:Mn></Mml:Msub></Mml:Math>.” Physical Review B 111, no. 10 (2025). https://doi.org/10.1103/physrevb.111.104103. ieee: 'A. Bocchini, U. Gerstmann, and W. G. Schmidt, “Microscopic origin of gray tracks in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>KTiOPO</mml:mi><mml:mn>4</mml:mn></mml:msub></mml:math>,” Physical Review B, vol. 111, no. 10, Art. no. 104103, 2025, doi: 10.1103/physrevb.111.104103.' mla: Bocchini, Adriana, et al. “Microscopic Origin of Gray Tracks in <mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML"><mml:Msub><mml:Mi>KTiOPO</Mml:Mi><mml:Mn>4</Mml:Mn></Mml:Msub></Mml:Math>.” Physical Review B, vol. 111, no. 10, 104103, American Physical Society (APS), 2025, doi:10.1103/physrevb.111.104103. short: A. Bocchini, U. Gerstmann, W.G. Schmidt, Physical Review B 111 (2025). date_created: 2025-07-09T08:58:32Z date_updated: 2025-07-09T09:30:31Z department: - _id: '15' - _id: '295' - _id: '790' - _id: '230' - _id: '429' - _id: '35' - _id: '170' - _id: '27' doi: 10.1103/physrevb.111.104103 intvolume: ' 111' issue: '10' language: - iso: eng project: - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '168' grant_number: '231447078' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' publication: Physical Review B publication_identifier: issn: - 2469-9950 - 2469-9969 publication_status: published publisher: American Physical Society (APS) status: public title: Microscopic origin of gray tracks in KTiOPO4 type: journal_article user_id: '16199' volume: 111 year: '2025' ... --- _id: '58642' abstract: - lang: eng text: We present a cost-effective self-assembly method to fabricate low-density dimer NPs in an NPoM architecture, using the M13 phage as a spacer layer. This will enable the development of dynamic plasmonic devices and advanced sensing applications. article_type: original author: - first_name: Vasanthan full_name: Devaraj, Vasanthan id: '103814' last_name: Devaraj - first_name: Isaac Azahel full_name: Ruiz Alvarado, Isaac Azahel id: '79462' last_name: Ruiz Alvarado orcid: 0000-0002-4710-1170 - first_name: Jong-Min full_name: Lee, Jong-Min last_name: Lee - first_name: Jin-Woo full_name: Oh, Jin-Woo last_name: Oh - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 citation: ama: Devaraj V, Ruiz Alvarado IA, Lee J-M, et al. Self-assembly of isolated plasmonic dimers with sub-5 nm gaps on a metallic mirror. Nanoscale Horizons. 2025;10:537-548. doi:10.1039/d4nh00546e apa: Devaraj, V., Ruiz Alvarado, I. A., Lee, J.-M., Oh, J.-W., Gerstmann, U., Schmidt, W. G., & Zentgraf, T. (2025). Self-assembly of isolated plasmonic dimers with sub-5 nm gaps on a metallic mirror. Nanoscale Horizons, 10, 537–548. https://doi.org/10.1039/d4nh00546e bibtex: '@article{Devaraj_Ruiz Alvarado_Lee_Oh_Gerstmann_Schmidt_Zentgraf_2025, title={Self-assembly of isolated plasmonic dimers with sub-5 nm gaps on a metallic mirror}, volume={10}, DOI={10.1039/d4nh00546e}, journal={Nanoscale Horizons}, publisher={Royal Society of Chemistry (RSC)}, author={Devaraj, Vasanthan and Ruiz Alvarado, Isaac Azahel and Lee, Jong-Min and Oh, Jin-Woo and Gerstmann, Uwe and Schmidt, Wolf Gero and Zentgraf, Thomas}, year={2025}, pages={537–548} }' chicago: 'Devaraj, Vasanthan, Isaac Azahel Ruiz Alvarado, Jong-Min Lee, Jin-Woo Oh, Uwe Gerstmann, Wolf Gero Schmidt, and Thomas Zentgraf. “Self-Assembly of Isolated Plasmonic Dimers with Sub-5 Nm Gaps on a Metallic Mirror.” Nanoscale Horizons 10 (2025): 537–48. https://doi.org/10.1039/d4nh00546e.' ieee: 'V. Devaraj et al., “Self-assembly of isolated plasmonic dimers with sub-5 nm gaps on a metallic mirror,” Nanoscale Horizons, vol. 10, pp. 537–548, 2025, doi: 10.1039/d4nh00546e.' mla: Devaraj, Vasanthan, et al. “Self-Assembly of Isolated Plasmonic Dimers with Sub-5 Nm Gaps on a Metallic Mirror.” Nanoscale Horizons, vol. 10, Royal Society of Chemistry (RSC), 2025, pp. 537–48, doi:10.1039/d4nh00546e. short: V. Devaraj, I.A. Ruiz Alvarado, J.-M. Lee, J.-W. Oh, U. Gerstmann, W.G. Schmidt, T. Zentgraf, Nanoscale Horizons 10 (2025) 537–548. date_created: 2025-02-14T08:13:10Z date_updated: 2025-07-09T14:04:39Z department: - _id: '15' - _id: '230' - _id: '289' - _id: '623' - _id: '35' - _id: '295' - _id: '170' - _id: '429' - _id: '27' doi: 10.1039/d4nh00546e intvolume: ' 10' language: - iso: eng page: 537-548 project: - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '168' grant_number: '231447078' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '445' grant_number: '367360193' name: Hochleistungsrechner Noctua in Paderborn - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Nanoscale Horizons publication_identifier: issn: - 2055-6756 - 2055-6764 publication_status: published publisher: Royal Society of Chemistry (RSC) quality_controlled: '1' status: public title: Self-assembly of isolated plasmonic dimers with sub-5 nm gaps on a metallic mirror type: journal_article user_id: '16199' volume: 10 year: '2025' ... --- _id: '61351' abstract: - lang: eng text: AbstractThe interaction of water molecules with semiconductor surfaces is relevant to various optoelectronic phenomena and physicochemical processes. Despite advances in fundamental understanding of water‐exposed surfaces, the detailed time‐ and energy‐resolved behavior of excited electrons remains largely unexplored. Here, the effects of water exposure on the near‐surface electron dynamics of phosphorus‐terminated p(2×2)/c(4×2)‐reconstructed indium phosphide (100) (P‐rich InP) are studied experimentally and matched to theoretical calculations. The P‐rich InP surface, consisting of H‐passivated P‐dimers, serves as a model for other P‐containing III‐V semiconductors such as gallium phosphide (GaP) or aluminum indium phosphide (AlInP). Electron dynamics near the surface are probed with femtosecond resolution using time‐resolved two‐photon photoemission (tr‐2PPE), a pump‐probe spectroscopic technique. Pulsed water exposure preserves electronic states and significantly increases lifetimes at the conduction band minimum (CBM). Density‐functional theory (DFT) calculations attribute these findings to suppression of surface vibrational modes in the top P‐layer by water exposure, reducing electronic transition probabilities of near‐band‐gap surface states. The results suggest that many near‐surface state lifetimes reported in ultra‐high vacuum may change significantly upon electrolyte exposure. These states may thus contribute more strongly to surface reactions than traditionally assumed. Demonstrating this effect for the technologically relevant P‐rich InP surface opens new opportunities in this underexplored area of surface electrochemistry. article_number: e00463 author: - first_name: Jonathan full_name: Diederich, Jonathan last_name: Diederich - first_name: Agnieszka full_name: Paszuk, Agnieszka last_name: Paszuk - first_name: Isaac Azahel full_name: Ruiz Alvarado, Isaac Azahel id: '79462' last_name: Ruiz Alvarado orcid: 0000-0002-4710-1170 - first_name: Marvin full_name: Krenz, Marvin last_name: Krenz - first_name: Mohammad Amin full_name: Zare Pour, Mohammad Amin last_name: Zare Pour - first_name: Diwakar Suresh full_name: Babu, Diwakar Suresh last_name: Babu - first_name: Jennifer full_name: Velazquez Rojas, Jennifer last_name: Velazquez Rojas - first_name: Christian full_name: Höhn, Christian last_name: Höhn - first_name: Yuying full_name: Gao, Yuying last_name: Gao - first_name: Klaus full_name: Schwarzburg, Klaus last_name: Schwarzburg - first_name: David full_name: Ostheimer, David last_name: Ostheimer - first_name: Rainer full_name: Eichberger, Rainer last_name: Eichberger - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Thomas full_name: Hannappel, Thomas last_name: Hannappel - first_name: Roel van full_name: de Krol, Roel van last_name: de Krol - first_name: Dennis full_name: Friedrich, Dennis last_name: Friedrich citation: ama: Diederich J, Paszuk A, Ruiz Alvarado IA, et al. Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface. Advanced Materials Interfaces. 2025;12(16). doi:10.1002/admi.202500463 apa: Diederich, J., Paszuk, A., Ruiz Alvarado, I. A., Krenz, M., Zare Pour, M. A., Babu, D. S., Velazquez Rojas, J., Höhn, C., Gao, Y., Schwarzburg, K., Ostheimer, D., Eichberger, R., Schmidt, W. G., Hannappel, T., de Krol, R. van, & Friedrich, D. (2025). Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface. Advanced Materials Interfaces, 12(16), Article e00463. https://doi.org/10.1002/admi.202500463 bibtex: '@article{Diederich_Paszuk_Ruiz Alvarado_Krenz_Zare Pour_Babu_Velazquez Rojas_Höhn_Gao_Schwarzburg_et al._2025, title={Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface}, volume={12}, DOI={10.1002/admi.202500463}, number={16e00463}, journal={Advanced Materials Interfaces}, publisher={Wiley}, author={Diederich, Jonathan and Paszuk, Agnieszka and Ruiz Alvarado, Isaac Azahel and Krenz, Marvin and Zare Pour, Mohammad Amin and Babu, Diwakar Suresh and Velazquez Rojas, Jennifer and Höhn, Christian and Gao, Yuying and Schwarzburg, Klaus and et al.}, year={2025} }' chicago: Diederich, Jonathan, Agnieszka Paszuk, Isaac Azahel Ruiz Alvarado, Marvin Krenz, Mohammad Amin Zare Pour, Diwakar Suresh Babu, Jennifer Velazquez Rojas, et al. “Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface.” Advanced Materials Interfaces 12, no. 16 (2025). https://doi.org/10.1002/admi.202500463. ieee: 'J. Diederich et al., “Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface,” Advanced Materials Interfaces, vol. 12, no. 16, Art. no. e00463, 2025, doi: 10.1002/admi.202500463.' mla: Diederich, Jonathan, et al. “Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface.” Advanced Materials Interfaces, vol. 12, no. 16, e00463, Wiley, 2025, doi:10.1002/admi.202500463. short: J. Diederich, A. Paszuk, I.A. Ruiz Alvarado, M. Krenz, M.A. Zare Pour, D.S. Babu, J. Velazquez Rojas, C. Höhn, Y. Gao, K. Schwarzburg, D. Ostheimer, R. Eichberger, W.G. Schmidt, T. Hannappel, R. van de Krol, D. Friedrich, Advanced Materials Interfaces 12 (2025). date_created: 2025-09-18T11:03:16Z date_updated: 2025-09-18T11:06:59Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '35' - _id: '230' - _id: '27' - _id: '429' doi: 10.1002/admi.202500463 intvolume: ' 12' issue: '16' language: - iso: eng project: - _id: '53' name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '55' name: TRR 142 - Project Area B - _id: '168' name: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*) - _id: '52' name: Computing Resources Provided by the Paderborn Center for Parallel Computing publication: Advanced Materials Interfaces publication_identifier: issn: - 2196-7350 - 2196-7350 publication_status: published publisher: Wiley status: public title: Ultrafast Electron Dynamics at the Water‐Modified InP(100) Surface type: journal_article user_id: '16199' volume: 12 year: '2025' ... --- _id: '61356' abstract: - lang: eng text: First-principles calculations reveal how topological defects in semiconducting carbon nanotubes trap triplet excitons and enable single-photon emission at telecom wavelengths, offering new insights into their potential for photonic devices. author: - first_name: Timur full_name: Biktagirov, Timur id: '65612' last_name: Biktagirov - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 citation: ama: Biktagirov T, Gerstmann U, Schmidt WG. Topological defects in semiconducting carbon nanotubes as triplet exciton traps and single-photon emitters. Nanoscale. 2025;17(11):6884-6891. doi:10.1039/d4nr03904a apa: Biktagirov, T., Gerstmann, U., & Schmidt, W. G. (2025). Topological defects in semiconducting carbon nanotubes as triplet exciton traps and single-photon emitters. Nanoscale, 17(11), 6884–6891. https://doi.org/10.1039/d4nr03904a bibtex: '@article{Biktagirov_Gerstmann_Schmidt_2025, title={Topological defects in semiconducting carbon nanotubes as triplet exciton traps and single-photon emitters}, volume={17}, DOI={10.1039/d4nr03904a}, number={11}, journal={Nanoscale}, publisher={Royal Society of Chemistry (RSC)}, author={Biktagirov, Timur and Gerstmann, Uwe and Schmidt, Wolf Gero}, year={2025}, pages={6884–6891} }' chicago: 'Biktagirov, Timur, Uwe Gerstmann, and Wolf Gero Schmidt. “Topological Defects in Semiconducting Carbon Nanotubes as Triplet Exciton Traps and Single-Photon Emitters.” Nanoscale 17, no. 11 (2025): 6884–91. https://doi.org/10.1039/d4nr03904a.' ieee: 'T. Biktagirov, U. Gerstmann, and W. G. Schmidt, “Topological defects in semiconducting carbon nanotubes as triplet exciton traps and single-photon emitters,” Nanoscale, vol. 17, no. 11, pp. 6884–6891, 2025, doi: 10.1039/d4nr03904a.' mla: Biktagirov, Timur, et al. “Topological Defects in Semiconducting Carbon Nanotubes as Triplet Exciton Traps and Single-Photon Emitters.” Nanoscale, vol. 17, no. 11, Royal Society of Chemistry (RSC), 2025, pp. 6884–91, doi:10.1039/d4nr03904a. short: T. Biktagirov, U. Gerstmann, W.G. Schmidt, Nanoscale 17 (2025) 6884–6891. date_created: 2025-09-18T11:23:25Z date_updated: 2025-09-18T11:26:23Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '790' - _id: '35' - _id: '230' - _id: '27' - _id: '429' doi: 10.1039/d4nr03904a intvolume: ' 17' issue: '11' language: - iso: eng page: 6884-6891 project: - _id: '52' name: Computing Resources Provided by the Paderborn Center for Parallel Computing - _id: '53' name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: TRR 142 - Project Area A - _id: '55' name: TRR 142 - Project Area B - _id: '168' name: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*) - _id: '166' name: TRR 142 - Subproject A11 publication: Nanoscale publication_identifier: issn: - 2040-3364 - 2040-3372 publication_status: published publisher: Royal Society of Chemistry (RSC) status: public title: Topological defects in semiconducting carbon nanotubes as triplet exciton traps and single-photon emitters type: journal_article user_id: '16199' volume: 17 year: '2025' ... --- _id: '60568' article_number: '122776' author: - first_name: Adriana full_name: Bocchini, Adriana id: '58349' last_name: Bocchini orcid: 0000-0002-2134-3075 - first_name: S. full_name: Kollmann, S. last_name: Kollmann - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Guido full_name: Grundmeier, Guido id: '194' last_name: Grundmeier citation: ama: Bocchini A, Kollmann S, Gerstmann U, Schmidt WG, Grundmeier G. Phosphonic acid adsorption on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si23.svg" display="inline" id="d1e564"><mml:mi>α</mml:mi></mml:math>-Bi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si24.svg" display="inline" id="d1e569"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>O<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si25.svg" display="inline" id="d1e577"><mml:msub><mml:mrow/><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:math> surfaces. Surface Science. 2025;760. doi:10.1016/j.susc.2025.122776 apa: Bocchini, A., Kollmann, S., Gerstmann, U., Schmidt, W. G., & Grundmeier, G. (2025). Phosphonic acid adsorption on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si23.svg" display="inline" id="d1e564"><mml:mi>α</mml:mi></mml:math>-Bi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si24.svg" display="inline" id="d1e569"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>O<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si25.svg" display="inline" id="d1e577"><mml:msub><mml:mrow/><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:math> surfaces. Surface Science, 760, Article 122776. https://doi.org/10.1016/j.susc.2025.122776 bibtex: '@article{Bocchini_Kollmann_Gerstmann_Schmidt_Grundmeier_2025, title={Phosphonic acid adsorption on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si23.svg" display="inline" id="d1e564"><mml:mi>α</mml:mi></mml:math>-Bi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si24.svg" display="inline" id="d1e569"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>O<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si25.svg" display="inline" id="d1e577"><mml:msub><mml:mrow/><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:math> surfaces}, volume={760}, DOI={10.1016/j.susc.2025.122776}, number={122776}, journal={Surface Science}, publisher={Elsevier BV}, author={Bocchini, Adriana and Kollmann, S. and Gerstmann, Uwe and Schmidt, Wolf Gero and Grundmeier, Guido}, year={2025} }' chicago: Bocchini, Adriana, S. Kollmann, Uwe Gerstmann, Wolf Gero Schmidt, and Guido Grundmeier. “Phosphonic Acid Adsorption on <mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML" Altimg="si23.Svg" Display="inline" Id="d1e564"><mml:Mi>α</Mml:Mi></Mml:Math>-Bi<mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML" Altimg="si24.Svg" Display="inline" Id="d1e569"><mml:Msub><mml:Mrow/><mml:Mrow><mml:Mn>2</Mml:Mn></Mml:Mrow></Mml:Msub></Mml:Math>O<mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML" Altimg="si25.Svg" Display="inline" Id="d1e577"><mml:Msub><mml:Mrow/><mml:Mrow><mml:Mn>3</Mml:Mn></Mml:Mrow></Mml:Msub></Mml:Math> Surfaces.” Surface Science 760 (2025). https://doi.org/10.1016/j.susc.2025.122776. ieee: 'A. Bocchini, S. Kollmann, U. Gerstmann, W. G. Schmidt, and G. Grundmeier, “Phosphonic acid adsorption on <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si23.svg" display="inline" id="d1e564"><mml:mi>α</mml:mi></mml:math>-Bi<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si24.svg" display="inline" id="d1e569"><mml:msub><mml:mrow/><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:math>O<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si25.svg" display="inline" id="d1e577"><mml:msub><mml:mrow/><mml:mrow><mml:mn>3</mml:mn></mml:mrow></mml:msub></mml:math> surfaces,” Surface Science, vol. 760, Art. no. 122776, 2025, doi: 10.1016/j.susc.2025.122776.' mla: Bocchini, Adriana, et al. “Phosphonic Acid Adsorption on <mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML" Altimg="si23.Svg" Display="inline" Id="d1e564"><mml:Mi>α</Mml:Mi></Mml:Math>-Bi<mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML" Altimg="si24.Svg" Display="inline" Id="d1e569"><mml:Msub><mml:Mrow/><mml:Mrow><mml:Mn>2</Mml:Mn></Mml:Mrow></Mml:Msub></Mml:Math>O<mml:Math Xmlns:Mml="http://Www.W3.Org/1998/Math/MathML" Altimg="si25.Svg" Display="inline" Id="d1e577"><mml:Msub><mml:Mrow/><mml:Mrow><mml:Mn>3</Mml:Mn></Mml:Mrow></Mml:Msub></Mml:Math> Surfaces.” Surface Science, vol. 760, 122776, Elsevier BV, 2025, doi:10.1016/j.susc.2025.122776. short: A. Bocchini, S. Kollmann, U. Gerstmann, W.G. Schmidt, G. Grundmeier, Surface Science 760 (2025). date_created: 2025-07-09T09:23:04Z date_updated: 2025-12-05T13:34:10Z department: - _id: '15' - _id: '2' - _id: '230' - _id: '295' - _id: '790' - _id: '302' - _id: '429' - _id: '35' - _id: '170' - _id: '27' doi: 10.1016/j.susc.2025.122776 intvolume: ' 760' language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.1016/j.susc.2025.122776 oa: '1' project: - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' - _id: '53' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '168' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' publication: Surface Science publication_identifier: issn: - 0039-6028 publication_status: published publisher: Elsevier BV status: public title: Phosphonic acid adsorption on α-Bi2O3 surfaces type: journal_article user_id: '16199' volume: 760 year: '2025' ... --- _id: '60566' article_number: '074402' author: - first_name: Adriana full_name: Bocchini, Adriana id: '58349' last_name: Bocchini orcid: 0000-0002-2134-3075 - first_name: Michael full_name: Rüsing, Michael id: '22501' last_name: Rüsing orcid: 0000-0003-4682-4577 - first_name: Laura full_name: Bollmers, Laura id: '61375' last_name: Bollmers - first_name: Sebastian full_name: Lengeling, Sebastian id: '44373' last_name: Lengeling - first_name: Philipp full_name: Mues, Philipp id: '49772' last_name: Mues orcid: 0000-0003-0643-7636 - first_name: Laura full_name: Padberg, Laura id: '40300' last_name: Padberg - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Christine full_name: Silberhorn, Christine id: '26263' last_name: Silberhorn - first_name: Christof full_name: Eigner, Christof id: '13244' last_name: Eigner orcid: https://orcid.org/0000-0002-5693-3083 - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 citation: ama: 'Bocchini A, Rüsing M, Bollmers L, et al. Mg dopants in lithium niobate: Defect models and impact on domain inversion. Physical Review Materials. 2025;9(7). doi:10.1103/5wz1-bjyr' apa: 'Bocchini, A., Rüsing, M., Bollmers, L., Lengeling, S., Mues, P., Padberg, L., Gerstmann, U., Silberhorn, C., Eigner, C., & Schmidt, W. G. (2025). Mg dopants in lithium niobate: Defect models and impact on domain inversion. Physical Review Materials, 9(7), Article 074402. https://doi.org/10.1103/5wz1-bjyr' bibtex: '@article{Bocchini_Rüsing_Bollmers_Lengeling_Mues_Padberg_Gerstmann_Silberhorn_Eigner_Schmidt_2025, title={Mg dopants in lithium niobate: Defect models and impact on domain inversion}, volume={9}, DOI={10.1103/5wz1-bjyr}, number={7074402}, journal={Physical Review Materials}, publisher={American Physical Society (APS)}, author={Bocchini, Adriana and Rüsing, Michael and Bollmers, Laura and Lengeling, Sebastian and Mues, Philipp and Padberg, Laura and Gerstmann, Uwe and Silberhorn, Christine and Eigner, Christof and Schmidt, Wolf Gero}, year={2025} }' chicago: 'Bocchini, Adriana, Michael Rüsing, Laura Bollmers, Sebastian Lengeling, Philipp Mues, Laura Padberg, Uwe Gerstmann, Christine Silberhorn, Christof Eigner, and Wolf Gero Schmidt. “Mg Dopants in Lithium Niobate: Defect Models and Impact on Domain Inversion.” Physical Review Materials 9, no. 7 (2025). https://doi.org/10.1103/5wz1-bjyr.' ieee: 'A. Bocchini et al., “Mg dopants in lithium niobate: Defect models and impact on domain inversion,” Physical Review Materials, vol. 9, no. 7, Art. no. 074402, 2025, doi: 10.1103/5wz1-bjyr.' mla: 'Bocchini, Adriana, et al. “Mg Dopants in Lithium Niobate: Defect Models and Impact on Domain Inversion.” Physical Review Materials, vol. 9, no. 7, 074402, American Physical Society (APS), 2025, doi:10.1103/5wz1-bjyr.' short: A. Bocchini, M. Rüsing, L. Bollmers, S. Lengeling, P. Mues, L. Padberg, U. Gerstmann, C. Silberhorn, C. Eigner, W.G. Schmidt, Physical Review Materials 9 (2025). date_created: 2025-07-09T09:13:24Z date_updated: 2026-03-17T17:50:06Z ddc: - '530' department: - _id: '15' - _id: '623' - _id: '295' - _id: '790' - _id: '288' - _id: '230' - _id: '429' - _id: '35' - _id: '170' - _id: '169' - _id: '27' doi: 10.1103/5wz1-bjyr file: - access_level: open_access content_type: application/pdf creator: adrianab date_created: 2025-07-09T09:18:45Z date_updated: 2025-07-10T06:43:34Z file_id: '60567' file_name: Mg_dopants_LN_PRM.pdf file_size: 4175120 relation: main_file file_date_updated: 2025-07-10T06:43:34Z has_accepted_license: '1' intvolume: ' 9' issue: '7' language: - iso: eng main_file_link: - open_access: '1' url: https://link.aps.org/doi/10.1103/5wz1-bjyr oa: '1' project: - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' - _id: '53' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '168' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' publication: Physical Review Materials publication_identifier: issn: - 2475-9953 publication_status: published publisher: American Physical Society (APS) status: public title: 'Mg dopants in lithium niobate: Defect models and impact on domain inversion' type: journal_article user_id: '22501' volume: 9 year: '2025' ... --- _id: '61255' abstract: - lang: eng text: "Abstract\r\n Topological states have been widely investigated in different types of systems and lattices. In the present work, we report on topological edge states in double-wave (DW) chains, which can be described by a generalized Aubry-André-Harper (AAH) model. For the specific system of a driven-dissipative exciton polariton system we show that in such potential chains, different types of edge states can form. For resonant optical excitation, we further find that the optical nonlinearity leads to a multistability of different edge states. This includes topologically protected edge states evolved directly from individual linear eigenstates as well as additional edge states that originate from nonlinearity-induced localization of bulk states. Extending the system into two dimensions (2D) by stacking horizontal DW chains in the vertical direction, we also create 2D multi-wave lattices. In such 2D lattices multiple Su–Schrieffer–Heeger (SSH) chains appear along the vertical direction. The combination of DW chains in the horizonal and SSH chains in the vertical direction then results in the formation of higher-order topological insulator corner states. Multistable corner states emerge in the nonlinear regime." author: - first_name: Tobias full_name: Schneider, Tobias last_name: Schneider - first_name: Wenlong full_name: Gao, Wenlong id: '78853' last_name: Gao - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 - first_name: Stefan full_name: Schumacher, Stefan id: '27271' last_name: Schumacher orcid: 0000-0003-4042-4951 - first_name: Xuekai full_name: Ma, Xuekai id: '59416' last_name: Ma citation: ama: Schneider T, Gao W, Zentgraf T, Schumacher S, Ma X. Topological edge and corner states in coupled wave lattices in nonlinear polariton condensates. Nanophotonics. 2024;13(4):509-518. doi:10.1515/nanoph-2023-0556 apa: Schneider, T., Gao, W., Zentgraf, T., Schumacher, S., & Ma, X. (2024). Topological edge and corner states in coupled wave lattices in nonlinear polariton condensates. Nanophotonics, 13(4), 509–518. https://doi.org/10.1515/nanoph-2023-0556 bibtex: '@article{Schneider_Gao_Zentgraf_Schumacher_Ma_2024, title={Topological edge and corner states in coupled wave lattices in nonlinear polariton condensates}, volume={13}, DOI={10.1515/nanoph-2023-0556}, number={4}, journal={Nanophotonics}, publisher={Walter de Gruyter GmbH}, author={Schneider, Tobias and Gao, Wenlong and Zentgraf, Thomas and Schumacher, Stefan and Ma, Xuekai}, year={2024}, pages={509–518} }' chicago: 'Schneider, Tobias, Wenlong Gao, Thomas Zentgraf, Stefan Schumacher, and Xuekai Ma. “Topological Edge and Corner States in Coupled Wave Lattices in Nonlinear Polariton Condensates.” Nanophotonics 13, no. 4 (2024): 509–18. https://doi.org/10.1515/nanoph-2023-0556.' ieee: 'T. Schneider, W. Gao, T. Zentgraf, S. Schumacher, and X. Ma, “Topological edge and corner states in coupled wave lattices in nonlinear polariton condensates,” Nanophotonics, vol. 13, no. 4, pp. 509–518, 2024, doi: 10.1515/nanoph-2023-0556.' mla: Schneider, Tobias, et al. “Topological Edge and Corner States in Coupled Wave Lattices in Nonlinear Polariton Condensates.” Nanophotonics, vol. 13, no. 4, Walter de Gruyter GmbH, 2024, pp. 509–18, doi:10.1515/nanoph-2023-0556. short: T. Schneider, W. Gao, T. Zentgraf, S. Schumacher, X. Ma, Nanophotonics 13 (2024) 509–518. date_created: 2025-09-12T11:19:22Z date_updated: 2025-09-12T11:22:41Z department: - _id: '15' - _id: '170' - _id: '297' - _id: '705' - _id: '35' - _id: '230' - _id: '429' - _id: '27' doi: 10.1515/nanoph-2023-0556 intvolume: ' 13' issue: '4' language: - iso: eng page: 509-518 project: - _id: '52' name: Computing Resources Provided by the Paderborn Center for Parallel Computing - _id: '53' name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: TRR 142 - Project Area A - _id: '55' name: TRR 142 - Project Area B - _id: '61' name: 'TRR 142; TP A04: Nichtlineare Quantenprozesstomographie und Photonik mit Polaritonen in Mikrokavitäten' - _id: '170' name: 'TRR 142; TP B09: Effiziente Erzeugung mit maßgeschneiderter optischer Phaselage der zweiten Harmonischen mittels Quasi-gebundener Zustände in GaAs Metaoberflächen' publication: Nanophotonics publication_identifier: issn: - 2192-8614 publication_status: published publisher: Walter de Gruyter GmbH status: public title: Topological edge and corner states in coupled wave lattices in nonlinear polariton condensates type: journal_article user_id: '16199' volume: 13 year: '2024' ... --- _id: '61357' author: - first_name: Marvin full_name: Krenz, Marvin last_name: Krenz - first_name: Simone full_name: Sanna, Simone last_name: Sanna - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 citation: ama: Krenz M, Sanna S, Gerstmann U, Schmidt WG. Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells. The Journal of Physical Chemistry C. 2024;128(41):17774-17778. doi:10.1021/acs.jpcc.4c05446 apa: Krenz, M., Sanna, S., Gerstmann, U., & Schmidt, W. G. (2024). Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells. The Journal of Physical Chemistry C, 128(41), 17774–17778. https://doi.org/10.1021/acs.jpcc.4c05446 bibtex: '@article{Krenz_Sanna_Gerstmann_Schmidt_2024, title={Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells}, volume={128}, DOI={10.1021/acs.jpcc.4c05446}, number={41}, journal={The Journal of Physical Chemistry C}, publisher={American Chemical Society (ACS)}, author={Krenz, Marvin and Sanna, Simone and Gerstmann, Uwe and Schmidt, Wolf Gero}, year={2024}, pages={17774–17778} }' chicago: 'Krenz, Marvin, Simone Sanna, Uwe Gerstmann, and Wolf Gero Schmidt. “Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells.” The Journal of Physical Chemistry C 128, no. 41 (2024): 17774–78. https://doi.org/10.1021/acs.jpcc.4c05446.' ieee: 'M. Krenz, S. Sanna, U. Gerstmann, and W. G. Schmidt, “Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells,” The Journal of Physical Chemistry C, vol. 128, no. 41, pp. 17774–17778, 2024, doi: 10.1021/acs.jpcc.4c05446.' mla: Krenz, Marvin, et al. “Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells.” The Journal of Physical Chemistry C, vol. 128, no. 41, American Chemical Society (ACS), 2024, pp. 17774–78, doi:10.1021/acs.jpcc.4c05446. short: M. Krenz, S. Sanna, U. Gerstmann, W.G. Schmidt, The Journal of Physical Chemistry C 128 (2024) 17774–17778. date_created: 2025-09-18T11:32:33Z date_updated: 2025-09-18T11:34:21Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '790' - _id: '230' - _id: '429' - _id: '35' - _id: '27' doi: 10.1021/acs.jpcc.4c05446 intvolume: ' 128' issue: '41' language: - iso: eng page: 17774-17778 project: - _id: '53' name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: TRR 142 - Project Area A - _id: '55' name: TRR 142 - Project Area B - _id: '166' name: TRR 142 - Subproject A11 - _id: '168' name: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*) - _id: '52' name: Computing Resources Provided by the Paderborn Center for Parallel Computing publication: The Journal of Physical Chemistry C publication_identifier: issn: - 1932-7447 - 1932-7455 publication_status: published publisher: American Chemical Society (ACS) status: public title: Understanding and Improving Triplet Exciton Transfer in Sensitized Silicon Solar Cells type: journal_article user_id: '16199' volume: 128 year: '2024' ... --- _id: '60581' abstract: - lang: eng text: "Abstract\r\n The natural band alignments between indium phosphide and the main dioxides of titanium, i.e. rutile, anatase, and brookite as well as amorphous titania are calculated from the branch-point energies of the respective materials. Irrespective of the titania polymorph considered, type-I band alignment is predicted. This may change, however, in dependence on the microscopic interface structure: supercell calculations for amorphous titania grown on P-rich InP(001) surfaces result in a titania conduction band that nearly aligns with that of InP. Depending on the interface specifics, both type-I band and type-II band alignments are observed in the simulations. This agrees with recent experimental findings." article_number: '075001' author: - first_name: Isaac Azahel full_name: Ruiz Alvarado, Isaac Azahel id: '79462' last_name: Ruiz Alvarado orcid: 0000-0002-4710-1170 - first_name: Christian full_name: Dreßler, Christian last_name: Dreßler - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 citation: ama: 'Ruiz Alvarado IA, Dreßler C, Schmidt WG. Band alignment at InP/TiO2 interfaces from density-functional theory. Journal of Physics: Condensed Matter. 2024;37(7). doi:10.1088/1361-648x/ad9725' apa: 'Ruiz Alvarado, I. A., Dreßler, C., & Schmidt, W. G. (2024). Band alignment at InP/TiO2 interfaces from density-functional theory. Journal of Physics: Condensed Matter, 37(7), Article 075001. https://doi.org/10.1088/1361-648x/ad9725' bibtex: '@article{Ruiz Alvarado_Dreßler_Schmidt_2024, title={Band alignment at InP/TiO2 interfaces from density-functional theory}, volume={37}, DOI={10.1088/1361-648x/ad9725}, number={7075001}, journal={Journal of Physics: Condensed Matter}, publisher={IOP Publishing}, author={Ruiz Alvarado, Isaac Azahel and Dreßler, Christian and Schmidt, Wolf Gero}, year={2024} }' chicago: 'Ruiz Alvarado, Isaac Azahel, Christian Dreßler, and Wolf Gero Schmidt. “Band Alignment at InP/TiO2 Interfaces from Density-Functional Theory.” Journal of Physics: Condensed Matter 37, no. 7 (2024). https://doi.org/10.1088/1361-648x/ad9725.' ieee: 'I. A. Ruiz Alvarado, C. Dreßler, and W. G. Schmidt, “Band alignment at InP/TiO2 interfaces from density-functional theory,” Journal of Physics: Condensed Matter, vol. 37, no. 7, Art. no. 075001, 2024, doi: 10.1088/1361-648x/ad9725.' mla: 'Ruiz Alvarado, Isaac Azahel, et al. “Band Alignment at InP/TiO2 Interfaces from Density-Functional Theory.” Journal of Physics: Condensed Matter, vol. 37, no. 7, 075001, IOP Publishing, 2024, doi:10.1088/1361-648x/ad9725.' short: 'I.A. Ruiz Alvarado, C. Dreßler, W.G. Schmidt, Journal of Physics: Condensed Matter 37 (2024).' date_created: 2025-07-09T13:40:51Z date_updated: 2025-12-05T13:35:44Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '230' - _id: '27' - _id: '35' doi: 10.1088/1361-648x/ad9725 intvolume: ' 37' issue: '7' language: - iso: eng project: - _id: '53' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '168' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' publication: 'Journal of Physics: Condensed Matter' publication_identifier: issn: - 0953-8984 - 1361-648X publication_status: published publisher: IOP Publishing status: public title: Band alignment at InP/TiO2 interfaces from density-functional theory type: journal_article user_id: '16199' volume: 37 year: '2024' ... --- _id: '54868' abstract: - lang: eng text: AbstractMost properties of solid materials are defined by their internal electric field and charge density distributions which so far are difficult to measure with high spatial resolution. Especially for 2D materials, the atomic electric fields influence the optoelectronic properties. In this study, the atomic‐scale electric field and charge density distribution of WSe2 bi‐ and trilayers are revealed using an emerging microscopy technique, differential phase contrast (DPC) imaging in scanning transmission electron microscopy (STEM). For pristine material, a higher positive charge density located at the selenium atomic columns compared to the tungsten atomic columns is obtained and tentatively explained by a coherent scattering effect. Furthermore, the change in the electric field distribution induced by a missing selenium atomic column is investigated. A characteristic electric field distribution in the vicinity of the defect with locally reduced magnitudes compared to the pristine lattice is observed. This effect is accompanied by a considerable inward relaxation of the surrounding lattice, which according to first principles DFT calculation is fully compatible with a missing column of Se atoms. This shows that DPC imaging, as an electric field sensitive technique, provides additional and remarkable information to the otherwise only structural analysis obtained with conventional STEM imaging. article_type: original author: - first_name: Maja full_name: Groll, Maja last_name: Groll - first_name: Julius full_name: Bürger, Julius id: '46952' last_name: Bürger - first_name: Ioannis full_name: Caltzidis, Ioannis id: '87911' last_name: Caltzidis - first_name: Klaus D. full_name: Jöns, Klaus D. id: '85353' last_name: Jöns - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Jörg K. N. full_name: Lindner, Jörg K. N. id: '20797' last_name: Lindner citation: ama: Groll M, Bürger J, Caltzidis I, et al. DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging. Small. Published online 2024. doi:10.1002/smll.202311635 apa: Groll, M., Bürger, J., Caltzidis, I., Jöns, K. D., Schmidt, W. G., Gerstmann, U., & Lindner, J. K. N. (2024). DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging. Small. https://doi.org/10.1002/smll.202311635 bibtex: '@article{Groll_Bürger_Caltzidis_Jöns_Schmidt_Gerstmann_Lindner_2024, title={DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging}, DOI={10.1002/smll.202311635}, journal={Small}, publisher={Wiley}, author={Groll, Maja and Bürger, Julius and Caltzidis, Ioannis and Jöns, Klaus D. and Schmidt, Wolf Gero and Gerstmann, Uwe and Lindner, Jörg K. N.}, year={2024} }' chicago: Groll, Maja, Julius Bürger, Ioannis Caltzidis, Klaus D. Jöns, Wolf Gero Schmidt, Uwe Gerstmann, and Jörg K. N. Lindner. “DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging.” Small, 2024. https://doi.org/10.1002/smll.202311635. ieee: 'M. Groll et al., “DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging,” Small, 2024, doi: 10.1002/smll.202311635.' mla: Groll, Maja, et al. “DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging.” Small, Wiley, 2024, doi:10.1002/smll.202311635. short: M. Groll, J. Bürger, I. Caltzidis, K.D. Jöns, W.G. Schmidt, U. Gerstmann, J.K.N. Lindner, Small (2024). date_created: 2024-06-24T09:46:25Z date_updated: 2025-12-05T13:39:01Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '790' - _id: '642' - _id: '286' - _id: '429' - _id: '230' - _id: '27' - _id: '35' - _id: '169' doi: 10.1002/smll.202311635 language: - iso: eng project: - _id: '53' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' - _id: '168' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Small publication_identifier: issn: - 1613-6810 - 1613-6829 publication_status: published publisher: Wiley status: public title: DFT‐Assisted Investigation of the Electric Field and Charge Density Distribution of Pristine and Defective 2D WSe2 by Differential Phase Contrast Imaging type: journal_article user_id: '16199' year: '2024' ... --- _id: '54856' abstract: - lang: eng text: "Abstract\r\n Theoretical spectroscopy based on double perturbation theory is typically challenged by systems with large orbital hyperfine splitting. Therefore, we here derive a rigorous, non-perturbative scheme starting from Dirac’s equation which allows to calculate the contribution of the orbital HFI for complex structures including heavy atoms with strong spin-orbit coupling (SOC). Using the PAW formalism, the method has been implemented in the software package Quantum ESPRESSO. We show that the ‘orbital part’ actually scales with SOC strength if orbital quenching is hindered by low local symmetry, i.e. in case of dimers or atoms at surfaces. This holds true in particular when the unpaired electron is localized in quasi-atomic p-like orbitals. Here, the orbital part is by far not negligible, but becomes dominant by surpassing the dipolar contribution by a factor of five." article_number: '012094' author: - first_name: Katharina full_name: Franzke, Katharina last_name: Franzke - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X citation: ama: 'Franzke K, Schmidt WG, Gerstmann U. Relativistic calculation of the orbital hyperfine splitting in complex microscopic structures. Journal of Physics: Conference Series. 2024;2701(1). doi:10.1088/1742-6596/2701/1/012094' apa: 'Franzke, K., Schmidt, W. G., & Gerstmann, U. (2024). Relativistic calculation of the orbital hyperfine splitting in complex microscopic structures. Journal of Physics: Conference Series, 2701(1), Article 012094. https://doi.org/10.1088/1742-6596/2701/1/012094' bibtex: '@article{Franzke_Schmidt_Gerstmann_2024, title={Relativistic calculation of the orbital hyperfine splitting in complex microscopic structures}, volume={2701}, DOI={10.1088/1742-6596/2701/1/012094}, number={1012094}, journal={Journal of Physics: Conference Series}, publisher={IOP Publishing}, author={Franzke, Katharina and Schmidt, Wolf Gero and Gerstmann, Uwe}, year={2024} }' chicago: 'Franzke, Katharina, Wolf Gero Schmidt, and Uwe Gerstmann. “Relativistic Calculation of the Orbital Hyperfine Splitting in Complex Microscopic Structures.” Journal of Physics: Conference Series 2701, no. 1 (2024). https://doi.org/10.1088/1742-6596/2701/1/012094.' ieee: 'K. Franzke, W. G. Schmidt, and U. Gerstmann, “Relativistic calculation of the orbital hyperfine splitting in complex microscopic structures,” Journal of Physics: Conference Series, vol. 2701, no. 1, Art. no. 012094, 2024, doi: 10.1088/1742-6596/2701/1/012094.' mla: 'Franzke, Katharina, et al. “Relativistic Calculation of the Orbital Hyperfine Splitting in Complex Microscopic Structures.” Journal of Physics: Conference Series, vol. 2701, no. 1, 012094, IOP Publishing, 2024, doi:10.1088/1742-6596/2701/1/012094.' short: 'K. Franzke, W.G. Schmidt, U. Gerstmann, Journal of Physics: Conference Series 2701 (2024).' date_created: 2024-06-24T06:26:02Z date_updated: 2025-12-05T13:36:01Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '790' - _id: '230' - _id: '429' - _id: '27' - _id: '35' doi: 10.1088/1742-6596/2701/1/012094 intvolume: ' 2701' issue: '1' language: - iso: eng project: - _id: '53' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' - _id: '168' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: 'Journal of Physics: Conference Series' publication_identifier: issn: - 1742-6588 - 1742-6596 publication_status: published publisher: IOP Publishing status: public title: Relativistic calculation of the orbital hyperfine splitting in complex microscopic structures type: journal_article user_id: '16199' volume: 2701 year: '2024' ... --- _id: '54865' article_number: '076201' author: - first_name: Marvin full_name: Krenz, Marvin id: '52309' last_name: Krenz - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 citation: ama: Krenz M, Gerstmann U, Schmidt WG. Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface. Physical Review Letters. 2024;132(7). doi:10.1103/physrevlett.132.076201 apa: Krenz, M., Gerstmann, U., & Schmidt, W. G. (2024). Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface. Physical Review Letters, 132(7), Article 076201. https://doi.org/10.1103/physrevlett.132.076201 bibtex: '@article{Krenz_Gerstmann_Schmidt_2024, title={Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface}, volume={132}, DOI={10.1103/physrevlett.132.076201}, number={7076201}, journal={Physical Review Letters}, publisher={American Physical Society (APS)}, author={Krenz, Marvin and Gerstmann, Uwe and Schmidt, Wolf Gero}, year={2024} }' chicago: Krenz, Marvin, Uwe Gerstmann, and Wolf Gero Schmidt. “Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface.” Physical Review Letters 132, no. 7 (2024). https://doi.org/10.1103/physrevlett.132.076201. ieee: 'M. Krenz, U. Gerstmann, and W. G. Schmidt, “Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface,” Physical Review Letters, vol. 132, no. 7, Art. no. 076201, 2024, doi: 10.1103/physrevlett.132.076201.' mla: Krenz, Marvin, et al. “Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface.” Physical Review Letters, vol. 132, no. 7, 076201, American Physical Society (APS), 2024, doi:10.1103/physrevlett.132.076201. short: M. Krenz, U. Gerstmann, W.G. Schmidt, Physical Review Letters 132 (2024). date_created: 2024-06-24T09:39:42Z date_updated: 2025-12-05T13:38:22Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '790' - _id: '429' - _id: '27' - _id: '230' - _id: '35' doi: 10.1103/physrevlett.132.076201 intvolume: ' 132' issue: '7' language: - iso: eng project: - _id: '53' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '168' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Physical Review Letters publication_identifier: issn: - 0031-9007 - 1079-7114 publication_status: published publisher: American Physical Society (APS) status: public title: Defect-Assisted Exciton Transfer across the Tetracene-Si(111):H Interface type: journal_article user_id: '16199' volume: 132 year: '2024' ... --- _id: '47997' abstract: - lang: eng text: The crystal family of potassium titanyl phosphate (KTiOPO4) is a promising material group for applications in quantum and nonlinear optics. The fabrication of low-loss optical waveguides, as well as high-grade periodically poled ferroelectric domain structures, requires a profound understanding of the material properties and crystal structure. In this regard, Raman spectroscopy offers the possibility to study and visualize domain structures, strain, defects, and the local stoichiometry, which are all factors impacting device performance. However, the accurate interpretation of Raman spectra and their changes with respect to extrinsic and intrinsic defects requires a thorough assignment of the Raman modes to their respective crystal features, which to date is only partly conducted based on phenomenological modelling. To address this issue, we calculated the phonon spectra of potassium titanyl phosphate and the related compounds rubidium titanyl phosphate (RbTiOPO4) and potassium titanyl arsenate (KTiOAsO4) based on density functional theory and compared them with experimental data. Overall, this allows us to assign various spectral features to eigenmodes of lattice substructures with improved detail compared to previous assignments. Nevertheless, the analysis also shows that not all features of the spectra can unambigiously be explained yet. A possible explanation might be that defects or long range fields not included in the modeling play a crucial rule for the resulting Raman spectrum. In conclusion, this work provides an improved foundation into the vibrational properties in the KTiOPO4 material family. article_number: '1423' author: - first_name: Sergej full_name: Neufeld, Sergej last_name: Neufeld - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X - first_name: Laura full_name: Padberg, Laura id: '40300' last_name: Padberg - first_name: Christof full_name: Eigner, Christof id: '13244' last_name: Eigner orcid: https://orcid.org/0000-0002-5693-3083 - first_name: Gerhard full_name: Berth, Gerhard id: '53' last_name: Berth - first_name: Christine full_name: Silberhorn, Christine id: '26263' last_name: Silberhorn - first_name: Lukas M. full_name: Eng, Lukas M. last_name: Eng - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Michael full_name: Rüsing, Michael id: '22501' last_name: Rüsing orcid: 0000-0003-4682-4577 citation: ama: Neufeld S, Gerstmann U, Padberg L, et al. Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family. Crystals. 2023;13(10). doi:10.3390/cryst13101423 apa: Neufeld, S., Gerstmann, U., Padberg, L., Eigner, C., Berth, G., Silberhorn, C., Eng, L. M., Schmidt, W. G., & Rüsing, M. (2023). Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family. Crystals, 13(10), Article 1423. https://doi.org/10.3390/cryst13101423 bibtex: '@article{Neufeld_Gerstmann_Padberg_Eigner_Berth_Silberhorn_Eng_Schmidt_Rüsing_2023, title={Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family}, volume={13}, DOI={10.3390/cryst13101423}, number={101423}, journal={Crystals}, publisher={MDPI AG}, author={Neufeld, Sergej and Gerstmann, Uwe and Padberg, Laura and Eigner, Christof and Berth, Gerhard and Silberhorn, Christine and Eng, Lukas M. and Schmidt, Wolf Gero and Rüsing, Michael}, year={2023} }' chicago: Neufeld, Sergej, Uwe Gerstmann, Laura Padberg, Christof Eigner, Gerhard Berth, Christine Silberhorn, Lukas M. Eng, Wolf Gero Schmidt, and Michael Rüsing. “Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family.” Crystals 13, no. 10 (2023). https://doi.org/10.3390/cryst13101423. ieee: 'S. Neufeld et al., “Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family,” Crystals, vol. 13, no. 10, Art. no. 1423, 2023, doi: 10.3390/cryst13101423.' mla: Neufeld, Sergej, et al. “Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family.” Crystals, vol. 13, no. 10, 1423, MDPI AG, 2023, doi:10.3390/cryst13101423. short: S. Neufeld, U. Gerstmann, L. Padberg, C. Eigner, G. Berth, C. Silberhorn, L.M. Eng, W.G. Schmidt, M. Rüsing, Crystals 13 (2023). date_created: 2023-10-11T09:10:53Z date_updated: 2023-10-11T09:15:58Z department: - _id: '169' doi: 10.3390/cryst13101423 funded_apc: '1' intvolume: ' 13' issue: '10' keyword: - Inorganic Chemistry - Condensed Matter Physics - General Materials Science - General Chemical Engineering language: - iso: eng main_file_link: - open_access: '1' url: https://doi.org/10.3390/cryst13101423 oa: '1' project: - _id: '168' grant_number: '231447078' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '266' grant_number: PROFILNRW-2020-067 name: 'PhoQC: PhoQC: Photonisches Quantencomputing' publication: Crystals publication_identifier: issn: - 2073-4352 publication_status: published publisher: MDPI AG quality_controlled: '1' status: public title: Vibrational Properties of the Potassium Titanyl Phosphate Crystal Family type: journal_article user_id: '22501' volume: 13 year: '2023' ... --- _id: '43246' abstract: - lang: eng text: The biexciton-exciton emission cascade commonly used in quantum-dot systems to generate polarization entanglement yields photons with intrinsically limited indistinguishability. In the present work we focus on the generation of pairs of photons with high degrees of polarization entanglement and simultaneously high indistinguishibility. We achieve this goal by selectively reducing the biexciton lifetime with an optical resonator. We demonstrate that a suitably tailored circular Bragg reflector fulfills the requirements of sufficient selective Purcell enhancement of biexciton emission paired with spectrally broad photon extraction and two-fold degenerate optical modes. Our in-depth theoretical study combines (i) the optimization of realistic photonic structures solving Maxwell's equations from which model parameters are extracted as input for (ii) microscopic simulations of quantum-dot cavity excitation dynamics with full access to photon properties. We report non-trivial dependencies on system parameters and use the predictive power of our combined theoretical approach to determine the optimal range of Purcell enhancement that maximizes indistinguishability and entanglement to near unity values in the telecom C-band at $1550\,\mathrm{nm}$. author: - first_name: David full_name: Bauch, David last_name: Bauch - first_name: Dustin full_name: Siebert, Dustin last_name: Siebert - first_name: Klaus full_name: Jöns, Klaus id: '85353' last_name: Jöns - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 - first_name: Stefan full_name: Schumacher, Stefan id: '27271' last_name: Schumacher orcid: 0000-0003-4042-4951 citation: ama: Bauch D, Siebert D, Jöns K, Förstner J, Schumacher S. On-demand indistinguishable and entangled photons at telecom frequencies using tailored cavity designs. Published online 2023. apa: Bauch, D., Siebert, D., Jöns, K., Förstner, J., & Schumacher, S. (2023). On-demand indistinguishable and entangled photons at telecom frequencies using tailored cavity designs. bibtex: '@article{Bauch_Siebert_Jöns_Förstner_Schumacher_2023, title={On-demand indistinguishable and entangled photons at telecom frequencies using tailored cavity designs}, author={Bauch, David and Siebert, Dustin and Jöns, Klaus and Förstner, Jens and Schumacher, Stefan}, year={2023} }' chicago: Bauch, David, Dustin Siebert, Klaus Jöns, Jens Förstner, and Stefan Schumacher. “On-Demand Indistinguishable and Entangled Photons at Telecom Frequencies Using Tailored Cavity Designs,” 2023. ieee: D. Bauch, D. Siebert, K. Jöns, J. Förstner, and S. Schumacher, “On-demand indistinguishable and entangled photons at telecom frequencies using tailored cavity designs.” 2023. mla: Bauch, David, et al. On-Demand Indistinguishable and Entangled Photons at Telecom Frequencies Using Tailored Cavity Designs. 2023. short: D. Bauch, D. Siebert, K. Jöns, J. Förstner, S. Schumacher, (2023). date_created: 2023-03-31T13:22:05Z date_updated: 2023-12-21T10:41:17Z department: - _id: '61' - _id: '230' - _id: '429' - _id: '623' - _id: '15' - _id: '35' - _id: '170' - _id: '297' keyword: - tet_topic_phc - tet_topic_qd language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/pdf/2303.13871.pdf oa: '1' project: - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' - _id: '173' grant_number: '231447078' name: 'TRR 142 - C09: TRR 142 - Subproject C09' - _id: '167' grant_number: '231447078' name: 'TRR 142 - B06: TRR 142 - Subproject B06' - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '56' name: 'TRR 142 - C: TRR 142 - Project Area C' related_material: record: - id: '48599' relation: later_version status: public status: public title: On-demand indistinguishable and entangled photons at telecom frequencies using tailored cavity designs type: preprint user_id: '16199' year: '2023' ... --- _id: '49607' abstract: - lang: eng text: In this work, we utilize thin dielectric meta-atoms placed on a silver substrate to efficiently enhance and manipulate the third-harmonic generation. We theoretically and experimentally reveal that when the structural symmetry of the meta-atom is incompatible with the lattice symmetry of an array, some generalized nonlinear geometric phases appear, which offers new possibilities for harmonic generation control beyond the accessible symmetries governed by the selection rule. The underlying mechanism is attributed to the modified rotation of the effective principal axis of a dense meta-atom array, where the strong coupling among the units gives rise to a generalized linear geometric phase modulation of the pump light. Therefore, nonlinear geometric phases carried by third-harmonic emissions are the natural result of the wave-mixing process among the modes excited at the fundamental frequency. This mechanism further points out a new strategy to predict the nonlinear geometric phases delivered by the nanostructures according to their linear responses. Our design is simple and efficient and offers alternatives for the nonlinear meta-devices that are capable of flexible photon generation and manipulation. article_type: original author: - first_name: Bingyi full_name: Liu, Bingyi last_name: Liu - first_name: René full_name: Geromel, René last_name: Geromel - first_name: Zhaoxian full_name: Su, Zhaoxian last_name: Su - first_name: Kai full_name: Guo, Kai last_name: Guo - first_name: Yongtian full_name: Wang, Yongtian last_name: Wang - first_name: Zhongyi full_name: Guo, Zhongyi last_name: Guo - first_name: Lingling full_name: Huang, Lingling last_name: Huang - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 citation: ama: Liu B, Geromel R, Su Z, et al. Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design. ACS Photonics. 2023;10(12):4357-4366. doi:10.1021/acsphotonics.3c01163 apa: Liu, B., Geromel, R., Su, Z., Guo, K., Wang, Y., Guo, Z., Huang, L., & Zentgraf, T. (2023). Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design. ACS Photonics, 10(12), 4357–4366. https://doi.org/10.1021/acsphotonics.3c01163 bibtex: '@article{Liu_Geromel_Su_Guo_Wang_Guo_Huang_Zentgraf_2023, title={Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design}, volume={10}, DOI={10.1021/acsphotonics.3c01163}, number={12}, journal={ACS Photonics}, publisher={American Chemical Society (ACS)}, author={Liu, Bingyi and Geromel, René and Su, Zhaoxian and Guo, Kai and Wang, Yongtian and Guo, Zhongyi and Huang, Lingling and Zentgraf, Thomas}, year={2023}, pages={4357–4366} }' chicago: 'Liu, Bingyi, René Geromel, Zhaoxian Su, Kai Guo, Yongtian Wang, Zhongyi Guo, Lingling Huang, and Thomas Zentgraf. “Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design.” ACS Photonics 10, no. 12 (2023): 4357–66. https://doi.org/10.1021/acsphotonics.3c01163.' ieee: 'B. Liu et al., “Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design,” ACS Photonics, vol. 10, no. 12, pp. 4357–4366, 2023, doi: 10.1021/acsphotonics.3c01163.' mla: Liu, Bingyi, et al. “Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design.” ACS Photonics, vol. 10, no. 12, American Chemical Society (ACS), 2023, pp. 4357–66, doi:10.1021/acsphotonics.3c01163. short: B. Liu, R. Geromel, Z. Su, K. Guo, Y. Wang, Z. Guo, L. Huang, T. Zentgraf, ACS Photonics 10 (2023) 4357–4366. date_created: 2023-12-13T14:11:41Z date_updated: 2024-04-16T06:47:40Z department: - _id: '15' - _id: '230' - _id: '289' - _id: '623' doi: 10.1021/acsphotonics.3c01163 funded_apc: '1' intvolume: ' 10' issue: '12' keyword: - Electrical and Electronic Engineering - Atomic and Molecular Physics - and Optics - Biotechnology - Electronic - Optical and Magnetic Materials language: - iso: eng main_file_link: - open_access: '1' url: https://pubs.acs.org/doi/full/10.1021/acsphotonics.3c01163 oa: '1' page: 4357-4366 project: - _id: '170' grant_number: '231447078' name: 'TRR 142 - B09: TRR 142 - Effiziente Erzeugung mit maßgeschneiderter optischer Phaselage der zweiten Harmonischen mittels Quasi-gebundener Zustände in GaAs Metaoberflächen (B09*)' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' publication: ACS Photonics publication_identifier: issn: - 2330-4022 - 2330-4022 publication_status: published publisher: American Chemical Society (ACS) quality_controlled: '1' status: public title: Nonlinear Dielectric Geometric-Phase Metasurface with Simultaneous Structure and Lattice Symmetry Design type: journal_article user_id: '30525' volume: 10 year: '2023' ... --- _id: '54854' abstract: - lang: eng text: 'Batteries based on heavier alkali ions are considered promising candidates to substitute for current Li-based technologies. In this theoretical study, we characterize the structural properties of a novel material, i.e., F-doped RbTiOPO4 (RbTiPO4F, RTP:F), and discuss aspects of its electrochemical performance in Rb-ion batteries (RIBs) using density functional theory (DFT). According to our calculations, RTP:F is expected to retain the so-called KTiOPO4 (KTP)-type structure, with lattice parameters of 13.236 Å, 6.616 Å, and 10.945 Å. Due to the doping with F, the crystal features eight extra electrons per unit cell, whereby each of these electrons is trapped by one of the surrounding Ti atoms in the cell. Notably, the ground state of the system corresponds to a ferromagnetic spin configuration (i.e., S=4). The deintercalation of Rb leads to the oxidation of the Ti atoms in the cell (i.e., from Ti3+ to Ti4+) and to reduced magnetic moments. The material promises interesting electrochemical properties for the cathode: rather high average voltages above 2.8 V and modest volume shrinkages below 13% even in the fully deintercalated case are predicted.' article_number: '5' author: - first_name: Adriana full_name: Bocchini, Adriana id: '58349' last_name: Bocchini orcid: 0000-0002-2134-3075 - first_name: Yingjie full_name: Xie, Yingjie last_name: Xie - first_name: Wolf Gero full_name: Schmidt, Wolf Gero id: '468' last_name: Schmidt orcid: 0000-0002-2717-5076 - first_name: Uwe full_name: Gerstmann, Uwe id: '171' last_name: Gerstmann orcid: 0000-0002-4476-223X citation: ama: Bocchini A, Xie Y, Schmidt WG, Gerstmann U. Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles. Crystals. 2023;14(1). doi:10.3390/cryst14010005 apa: Bocchini, A., Xie, Y., Schmidt, W. G., & Gerstmann, U. (2023). Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles. Crystals, 14(1), Article 5. https://doi.org/10.3390/cryst14010005 bibtex: '@article{Bocchini_Xie_Schmidt_Gerstmann_2023, title={Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles}, volume={14}, DOI={10.3390/cryst14010005}, number={15}, journal={Crystals}, publisher={MDPI AG}, author={Bocchini, Adriana and Xie, Yingjie and Schmidt, Wolf Gero and Gerstmann, Uwe}, year={2023} }' chicago: Bocchini, Adriana, Yingjie Xie, Wolf Gero Schmidt, and Uwe Gerstmann. “Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles.” Crystals 14, no. 1 (2023). https://doi.org/10.3390/cryst14010005. ieee: 'A. Bocchini, Y. Xie, W. G. Schmidt, and U. Gerstmann, “Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles,” Crystals, vol. 14, no. 1, Art. no. 5, 2023, doi: 10.3390/cryst14010005.' mla: Bocchini, Adriana, et al. “Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles.” Crystals, vol. 14, no. 1, 5, MDPI AG, 2023, doi:10.3390/cryst14010005. short: A. Bocchini, Y. Xie, W.G. Schmidt, U. Gerstmann, Crystals 14 (2023). date_created: 2024-06-24T06:21:04Z date_updated: 2024-06-24T06:30:13Z department: - _id: '15' - _id: '170' - _id: '295' - _id: '790' - _id: '230' - _id: '429' - _id: '27' doi: 10.3390/cryst14010005 intvolume: ' 14' issue: '1' language: - iso: eng project: - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '54' name: 'TRR 142 - A: TRR 142 - Project Area A' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '166' name: 'TRR 142 - A11: TRR 142 - Subproject A11' - _id: '168' grant_number: '231447078' name: 'TRR 142 - B07: TRR 142 - Polaronen-Einfluss auf die optischen Eigenschaften von Lithiumniobat (B07*)' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Crystals publication_identifier: issn: - 2073-4352 publication_status: published publisher: MDPI AG status: public title: Structural and Electrochemical Properties of F-Doped RbTiOPO4 (RTP:F) Predicted from First Principles type: journal_article user_id: '16199' volume: 14 year: '2023' ... --- _id: '50012' abstract: - lang: eng text: Silicon photonics, in conjunction with complementary metal-oxide-semiconductor (CMOS) fabrication, has greatly enhanced the development of integrated optical phased arrays. This facilitates a dynamic control of light in a compact form factor that enables the synthesis of arbitrary complex wavefronts in the infrared spectrum. We numerically demonstrate a large-scale two-dimensional silicon-based optical phased array (OPA) composed of nanoantennas with circular gratings that are balanced in power and aligned in phase, required for producing elegant radiation patterns in the far-field. For a wavelength of 1.55 μm, we optimize two antennas for the OPA exhibiting an upward radiation efficiency as high as 90%, with almost 6.8% of optical power concentrated in the field of view. Additionally, we believe that the proposed OPAs can be easily fabricated and would have the ability to generate complex holographic images, rendering them an attractive candidate for a wide range of applications like LiDAR sensors, optical trapping, optogenetic stimulation, and augmented-reality displays. author: - first_name: Henna full_name: Farheen, Henna id: '53444' last_name: Farheen orcid: 0000-0001-7730-3489 - first_name: Andreas full_name: Strauch, Andreas last_name: Strauch - first_name: J. Christoph full_name: Scheytt, J. Christoph id: '37144' last_name: Scheytt orcid: '0000-0002-5950-6618 ' - first_name: Viktor full_name: Myroshnychenko, Viktor id: '46371' last_name: Myroshnychenko - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 citation: ama: Farheen H, Strauch A, Scheytt JC, Myroshnychenko V, Förstner J. Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays. Photonics and Nanostructures - Fundamentals and Applications. 2023;58:101207. doi:10.1016/j.photonics.2023.101207 apa: Farheen, H., Strauch, A., Scheytt, J. C., Myroshnychenko, V., & Förstner, J. (2023). Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays. Photonics and Nanostructures - Fundamentals and Applications, 58, 101207. https://doi.org/10.1016/j.photonics.2023.101207 bibtex: '@article{Farheen_Strauch_Scheytt_Myroshnychenko_Förstner_2023, title={Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays}, volume={58}, DOI={10.1016/j.photonics.2023.101207}, journal={Photonics and Nanostructures - Fundamentals and Applications}, publisher={Elsevier BV}, author={Farheen, Henna and Strauch, Andreas and Scheytt, J. Christoph and Myroshnychenko, Viktor and Förstner, Jens}, year={2023}, pages={101207} }' chicago: 'Farheen, Henna, Andreas Strauch, J. Christoph Scheytt, Viktor Myroshnychenko, and Jens Förstner. “Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays.” Photonics and Nanostructures - Fundamentals and Applications 58 (2023): 101207. https://doi.org/10.1016/j.photonics.2023.101207.' ieee: 'H. Farheen, A. Strauch, J. C. Scheytt, V. Myroshnychenko, and J. Förstner, “Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays,” Photonics and Nanostructures - Fundamentals and Applications, vol. 58, p. 101207, 2023, doi: 10.1016/j.photonics.2023.101207.' mla: Farheen, Henna, et al. “Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays.” Photonics and Nanostructures - Fundamentals and Applications, vol. 58, Elsevier BV, 2023, p. 101207, doi:10.1016/j.photonics.2023.101207. short: H. Farheen, A. Strauch, J.C. Scheytt, V. Myroshnychenko, J. Förstner, Photonics and Nanostructures - Fundamentals and Applications 58 (2023) 101207. date_created: 2023-12-21T09:30:03Z date_updated: 2024-07-22T07:44:33Z ddc: - '530' department: - _id: '61' - _id: '230' - _id: '429' - _id: '58' doi: 10.1016/j.photonics.2023.101207 file: - access_level: open_access content_type: application/pdf creator: fossie date_created: 2023-12-21T09:34:17Z date_updated: 2023-12-21T09:34:17Z file_id: '50013' file_name: 2ß23-12 Farheen - PNFA - Optimized, highly efficient silicon antennas for optical phased arrays.pdf file_size: 3339442 relation: main_file file_date_updated: 2023-12-21T09:34:17Z has_accepted_license: '1' intvolume: ' 58' keyword: - tet_topic_opticalantenna language: - iso: eng oa: '1' page: '101207' project: - _id: '266' grant_number: PROFILNRW-2020-067 name: 'PhoQC: PhoQC: Photonisches Quantencomputing' - _id: '167' grant_number: '231447078' name: 'TRR 142 - B06: TRR 142 - Ultraschnelle kohärente opto-elektronische Kontrolle eines photonischen Quantensystems (B06*)' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Photonics and Nanostructures - Fundamentals and Applications publication_identifier: issn: - 1569-4410 publication_status: published publisher: Elsevier BV related_material: link: - relation: research_data url: https://doi.org/10.5281/zenodo.10044122 status: public title: Optimized, Highly Efficient Silicon Antennas for Optical Phased Arrays type: journal_article user_id: '158' volume: 58 year: '2023' ... --- _id: '43245' abstract: - lang: eng text: High-contrast slab waveguide Bragg gratings with 1D periodicity are investigated. For specific oblique excitation by semi-guided waves at sufficiently high angles of incidence, the idealized structures do not exhibit any radiative losses, such that reflectance and transmittance for the single port mode add strictly up to one. We consider a series of symmetric, fully and partly etched finite gratings, for parameters found in integrated silicon photonics. These can act as spectral filters with a reasonably flattop response. Apodization can lead to more box shaped reflectance and transmittance spectra. Together with a narrowband Fabry–Perot filter, these configurations are characterized by reflection bands, or transmittance peaks, with widths that span three orders of magnitude. author: - first_name: Manfred full_name: Hammer, Manfred id: '48077' last_name: Hammer orcid: 0000-0002-6331-9348 - first_name: Henna full_name: Farheen, Henna id: '53444' last_name: Farheen orcid: 0000-0001-7730-3489 - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 citation: ama: Hammer M, Farheen H, Förstner J. How to suppress radiative losses in high-contrast integrated Bragg gratings. Journal of the Optical Society of America B. 2023;40(4):862. doi:10.1364/josab.485725 apa: Hammer, M., Farheen, H., & Förstner, J. (2023). How to suppress radiative losses in high-contrast integrated Bragg gratings. Journal of the Optical Society of America B, 40(4), 862. https://doi.org/10.1364/josab.485725 bibtex: '@article{Hammer_Farheen_Förstner_2023, title={How to suppress radiative losses in high-contrast integrated Bragg gratings}, volume={40}, DOI={10.1364/josab.485725}, number={4}, journal={Journal of the Optical Society of America B}, publisher={Optica Publishing Group}, author={Hammer, Manfred and Farheen, Henna and Förstner, Jens}, year={2023}, pages={862} }' chicago: 'Hammer, Manfred, Henna Farheen, and Jens Förstner. “How to Suppress Radiative Losses in High-Contrast Integrated Bragg Gratings.” Journal of the Optical Society of America B 40, no. 4 (2023): 862. https://doi.org/10.1364/josab.485725.' ieee: 'M. Hammer, H. Farheen, and J. Förstner, “How to suppress radiative losses in high-contrast integrated Bragg gratings,” Journal of the Optical Society of America B, vol. 40, no. 4, p. 862, 2023, doi: 10.1364/josab.485725.' mla: Hammer, Manfred, et al. “How to Suppress Radiative Losses in High-Contrast Integrated Bragg Gratings.” Journal of the Optical Society of America B, vol. 40, no. 4, Optica Publishing Group, 2023, p. 862, doi:10.1364/josab.485725. short: M. Hammer, H. Farheen, J. Förstner, Journal of the Optical Society of America B 40 (2023) 862. date_created: 2023-03-31T13:04:43Z date_updated: 2024-07-22T07:44:38Z ddc: - '530' department: - _id: '61' - _id: '230' - _id: '429' doi: 10.1364/josab.485725 file: - access_level: open_access content_type: application/pdf creator: fossie date_created: 2023-03-31T13:14:59Z date_updated: 2023-03-31T13:14:59Z file_id: '43247' file_name: ogr-afterreview.pdf file_size: 1982311 relation: main_file file_date_updated: 2023-03-31T13:14:59Z has_accepted_license: '1' intvolume: ' 40' issue: '4' keyword: - tet_topic_waveguide language: - iso: eng oa: '1' page: '862' project: - _id: '53' grant_number: '231447078' name: 'TRR 142: TRR 142' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '167' grant_number: '231447078' name: 'TRR 142 - B06: TRR 142 - Subproject B06' publication: Journal of the Optical Society of America B publication_identifier: issn: - 0740-3224 - 1520-8540 publication_status: published publisher: Optica Publishing Group status: public title: How to suppress radiative losses in high-contrast integrated Bragg gratings type: journal_article user_id: '158' volume: 40 year: '2023' ...