--- _id: '52700' abstract: - lang: eng text: 'We explore the polarization hysteretic behaviour and field-dependent permittivity of ferroelectric-dielectric 2D materials formed by random dispersions of low permittivity inclusions in a ferroelectric matrix, using finite element simulations. We show how the degree of impenetrability of dielectric inclusions plays a substantial role in controlling the coercive field, remnant and saturation polarizations of the homogenized materials. The results highlight the significance of the degree of impenetrability of inclusion in tuning the effective polarization properties of such ferroelectric composites: coercive field drops significantly as percolation threshold is attained and remnant polarization decreases faster than a linear decay.' author: - first_name: Viktor full_name: Myroshnychenko, Viktor id: '46371' last_name: Myroshnychenko - first_name: Pious Mathews full_name: Mulavarickal Jose, Pious Mathews last_name: Mulavarickal Jose - first_name: Henna full_name: Farheen, Henna last_name: Farheen - first_name: Shafaq full_name: Ejaz, Shafaq last_name: Ejaz - first_name: Christian full_name: Brosseau, Christian last_name: Brosseau - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 citation: ama: 'Myroshnychenko V, Mulavarickal Jose PM, Farheen H, Ejaz S, Brosseau C, Förstner J. From Swiss-cheese to discrete ferroelectric composites: assessing the ferroelectric butterfly shape in polarization loops. Physica Scripta. 2024;99(4):045952. doi:10.1088/1402-4896/ad3172' apa: 'Myroshnychenko, V., Mulavarickal Jose, P. M., Farheen, H., Ejaz, S., Brosseau, C., & Förstner, J. (2024). From Swiss-cheese to discrete ferroelectric composites: assessing the ferroelectric butterfly shape in polarization loops. Physica Scripta, 99(4), 045952. https://doi.org/10.1088/1402-4896/ad3172' bibtex: '@article{Myroshnychenko_Mulavarickal Jose_Farheen_Ejaz_Brosseau_Förstner_2024, title={From Swiss-cheese to discrete ferroelectric composites: assessing the ferroelectric butterfly shape in polarization loops}, volume={99}, DOI={10.1088/1402-4896/ad3172}, number={4}, journal={Physica Scripta}, publisher={IOP Publishing}, author={Myroshnychenko, Viktor and Mulavarickal Jose, Pious Mathews and Farheen, Henna and Ejaz, Shafaq and Brosseau, Christian and Förstner, Jens}, year={2024}, pages={045952} }' chicago: 'Myroshnychenko, Viktor, Pious Mathews Mulavarickal Jose, Henna Farheen, Shafaq Ejaz, Christian Brosseau, and Jens Förstner. “From Swiss-Cheese to Discrete Ferroelectric Composites: Assessing the Ferroelectric Butterfly Shape in Polarization Loops.” Physica Scripta 99, no. 4 (2024): 045952. https://doi.org/10.1088/1402-4896/ad3172.' ieee: 'V. Myroshnychenko, P. M. Mulavarickal Jose, H. Farheen, S. Ejaz, C. Brosseau, and J. Förstner, “From Swiss-cheese to discrete ferroelectric composites: assessing the ferroelectric butterfly shape in polarization loops,” Physica Scripta, vol. 99, no. 4, p. 045952, 2024, doi: 10.1088/1402-4896/ad3172.' mla: 'Myroshnychenko, Viktor, et al. “From Swiss-Cheese to Discrete Ferroelectric Composites: Assessing the Ferroelectric Butterfly Shape in Polarization Loops.” Physica Scripta, vol. 99, no. 4, IOP Publishing, 2024, p. 045952, doi:10.1088/1402-4896/ad3172.' short: V. Myroshnychenko, P.M. Mulavarickal Jose, H. Farheen, S. Ejaz, C. Brosseau, J. Förstner, Physica Scripta 99 (2024) 045952. date_created: 2024-03-21T10:34:48Z date_updated: 2024-03-21T10:40:51Z ddc: - '530' department: - _id: '61' - _id: '230' doi: 10.1088/1402-4896/ad3172 file: - access_level: open_access content_type: application/pdf creator: fossie date_created: 2024-03-21T10:39:32Z date_updated: 2024-03-21T10:39:32Z file_id: '52701' file_name: 2024-03 Myroshnychenko - Physica Scripta - From Swiss-cheese to discrete ferroelectric.pdf file_size: 5386508 relation: main_file file_date_updated: 2024-03-21T10:39:32Z has_accepted_license: '1' intvolume: ' 99' issue: '4' keyword: - tet_topic_ferro language: - iso: eng oa: '1' page: '045952' project: - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Physica Scripta publication_identifier: issn: - 0031-8949 - 1402-4896 publication_status: published publisher: IOP Publishing status: public title: 'From Swiss-cheese to discrete ferroelectric composites: assessing the ferroelectric butterfly shape in polarization loops' type: journal_article user_id: '158' volume: 99 year: '2024' ... --- _id: '43018' article_number: '108557' author: - first_name: Samer full_name: Alhaddad, Samer id: '42456' last_name: Alhaddad - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 - first_name: Yevgen full_name: Grynko, Yevgen id: '26059' last_name: Grynko citation: ama: Alhaddad S, Förstner J, Grynko Y. Numerical study of light backscattering from layers of absorbing irregular particles larger than the wavelength. Journal of Quantitative Spectroscopy and Radiative Transfer. 2023;302. doi:10.1016/j.jqsrt.2023.108557 apa: Alhaddad, S., Förstner, J., & Grynko, Y. (2023). Numerical study of light backscattering from layers of absorbing irregular particles larger than the wavelength. Journal of Quantitative Spectroscopy and Radiative Transfer, 302, Article 108557. https://doi.org/10.1016/j.jqsrt.2023.108557 bibtex: '@article{Alhaddad_Förstner_Grynko_2023, title={Numerical study of light backscattering from layers of absorbing irregular particles larger than the wavelength}, volume={302}, DOI={10.1016/j.jqsrt.2023.108557}, number={108557}, journal={Journal of Quantitative Spectroscopy and Radiative Transfer}, publisher={Elsevier BV}, author={Alhaddad, Samer and Förstner, Jens and Grynko, Yevgen}, year={2023} }' chicago: Alhaddad, Samer, Jens Förstner, and Yevgen Grynko. “Numerical Study of Light Backscattering from Layers of Absorbing Irregular Particles Larger than the Wavelength.” Journal of Quantitative Spectroscopy and Radiative Transfer 302 (2023). https://doi.org/10.1016/j.jqsrt.2023.108557. ieee: 'S. Alhaddad, J. Förstner, and Y. Grynko, “Numerical study of light backscattering from layers of absorbing irregular particles larger than the wavelength,” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 302, Art. no. 108557, 2023, doi: 10.1016/j.jqsrt.2023.108557.' mla: Alhaddad, Samer, et al. “Numerical Study of Light Backscattering from Layers of Absorbing Irregular Particles Larger than the Wavelength.” Journal of Quantitative Spectroscopy and Radiative Transfer, vol. 302, 108557, Elsevier BV, 2023, doi:10.1016/j.jqsrt.2023.108557. short: S. Alhaddad, J. Förstner, Y. Grynko, Journal of Quantitative Spectroscopy and Radiative Transfer 302 (2023). date_created: 2023-03-14T12:32:54Z date_updated: 2023-03-15T17:36:13Z ddc: - '530' department: - _id: '61' doi: 10.1016/j.jqsrt.2023.108557 file: - access_level: local content_type: application/pdf creator: fossie date_created: 2023-03-15T15:58:15Z date_updated: 2023-03-15T15:58:15Z file_id: '43028' file_name: 2023-03 Alhaddad - JQSRT - Numerical study of light backscattering from layers of absorbing particles larger than the wavelength.pdf file_size: 1508833 relation: main_file - access_level: open_access content_type: application/pdf creator: fossie date_created: 2023-03-15T17:35:29Z date_updated: 2023-03-15T17:35:29Z file_id: '43029' file_name: 2023-03 Alhaddad - JQSRT - Numerical study of light backscattering from layers of absorbing particles larger than the wavelength (accepted manuscript).pdf file_size: 4254386 relation: main_file file_date_updated: 2023-03-15T17:35:29Z has_accepted_license: '1' intvolume: ' 302' keyword: - tet_topic_scattering language: - iso: eng license: https://creativecommons.org/licenses/by-nc-nd/4.0/ oa: '1' project: - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Journal of Quantitative Spectroscopy and Radiative Transfer publication_identifier: issn: - 0022-4073 publication_status: published publisher: Elsevier BV status: public title: Numerical study of light backscattering from layers of absorbing irregular particles larger than the wavelength type: journal_article user_id: '158' volume: 302 year: '2023' ... --- _id: '43051' abstract: - lang: eng text: We demonstrate the numerical and experimental realization of optimized optical traveling-wave antennas made of low-loss dielectric materials. These antennas exhibit highly directive radiation patterns and our studies reveal that this nature comes from two dominant guided TE modes excited in the waveguide-like director of the antenna, in addition to the leaky modes. The optimized antennas possess a broadband nature and have a nearunity radiation efficiency at an operational wavelength of 780 nm. Compared to the previously studied plasmonic antennas for photon emission, our all-dielectric approach demonstrates a new class of highly directional, low-loss, and broadband optical antennas. author: - first_name: Henna full_name: Farheen, Henna last_name: Farheen - first_name: Lok-Yee full_name: Yan, Lok-Yee last_name: Yan - first_name: Till full_name: Leuteritz, Till last_name: Leuteritz - first_name: Siqi full_name: Qiao, Siqi last_name: Qiao - first_name: Florian full_name: Spreyer, Florian last_name: Spreyer - first_name: Christian full_name: Schlickriede, Christian last_name: Schlickriede - first_name: Viktor full_name: Quiring, Viktor last_name: Quiring - first_name: Christof full_name: Eigner, Christof last_name: Eigner - first_name: Christine full_name: Silberhorn, Christine id: '26263' last_name: Silberhorn - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 - first_name: Stefan full_name: Linden, Stefan last_name: Linden - 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, Yan L-Y, Leuteritz T, et al. Tailoring the directive nature of optical waveguide antennas. In: García-Blanco SM, Cheben P, eds. Integrated Optics: Devices, Materials, and Technologies XXVII. SPIE; 2023:124241E. doi:10.1117/12.2658921' apa: 'Farheen, H., Yan, L.-Y., Leuteritz, T., Qiao, S., Spreyer, F., Schlickriede, C., Quiring, V., Eigner, C., Silberhorn, C., Zentgraf, T., Linden, S., Myroshnychenko, V., & Förstner, J. (2023). Tailoring the directive nature of optical waveguide antennas. In S. M. García-Blanco & P. Cheben (Eds.), Integrated Optics: Devices, Materials, and Technologies XXVII (p. 124241E). SPIE. https://doi.org/10.1117/12.2658921' bibtex: '@inproceedings{Farheen_Yan_Leuteritz_Qiao_Spreyer_Schlickriede_Quiring_Eigner_Silberhorn_Zentgraf_et al._2023, title={Tailoring the directive nature of optical waveguide antennas}, DOI={10.1117/12.2658921}, booktitle={Integrated Optics: Devices, Materials, and Technologies XXVII}, publisher={SPIE}, author={Farheen, Henna and Yan, Lok-Yee and Leuteritz, Till and Qiao, Siqi and Spreyer, Florian and Schlickriede, Christian and Quiring, Viktor and Eigner, Christof and Silberhorn, Christine and Zentgraf, Thomas and et al.}, editor={García-Blanco, Sonia M. and Cheben, Pavel}, year={2023}, pages={124241E} }' chicago: 'Farheen, Henna, Lok-Yee Yan, Till Leuteritz, Siqi Qiao, Florian Spreyer, Christian Schlickriede, Viktor Quiring, et al. “Tailoring the Directive Nature of Optical Waveguide Antennas.” In Integrated Optics: Devices, Materials, and Technologies XXVII, edited by Sonia M. García-Blanco and Pavel Cheben, 124241E. SPIE, 2023. https://doi.org/10.1117/12.2658921.' ieee: 'H. Farheen et al., “Tailoring the directive nature of optical waveguide antennas,” in Integrated Optics: Devices, Materials, and Technologies XXVII, 2023, p. 124241E, doi: 10.1117/12.2658921.' mla: 'Farheen, Henna, et al. “Tailoring the Directive Nature of Optical Waveguide Antennas.” Integrated Optics: Devices, Materials, and Technologies XXVII, edited by Sonia M. García-Blanco and Pavel Cheben, SPIE, 2023, p. 124241E, doi:10.1117/12.2658921.' short: 'H. Farheen, L.-Y. Yan, T. Leuteritz, S. Qiao, F. Spreyer, C. Schlickriede, V. Quiring, C. Eigner, C. Silberhorn, T. Zentgraf, S. Linden, V. Myroshnychenko, J. Förstner, in: S.M. García-Blanco, P. Cheben (Eds.), Integrated Optics: Devices, Materials, and Technologies XXVII, SPIE, 2023, p. 124241E.' date_created: 2023-03-21T12:28:31Z date_updated: 2023-03-22T09:26:25Z ddc: - '530' department: - _id: '61' - _id: '230' - _id: '429' doi: 10.1117/12.2658921 editor: - first_name: Sonia M. full_name: García-Blanco, Sonia M. last_name: García-Blanco - first_name: Pavel full_name: Cheben, Pavel last_name: Cheben file: - access_level: local content_type: application/pdf creator: fossie date_created: 2023-03-22T09:25:57Z date_updated: 2023-03-22T09:25:57Z file_id: '43062' file_name: 2023-01 Poster Photonics West Henna OWA_A0.pdf file_size: 1426599 relation: main_file file_date_updated: 2023-03-22T09:25:57Z has_accepted_license: '1' keyword: - tet_topic_opticalantenna language: - iso: eng page: 124241E publication: 'Integrated Optics: Devices, Materials, and Technologies XXVII' publication_status: published publisher: SPIE status: public title: Tailoring the directive nature of optical waveguide antennas type: conference user_id: '158' year: '2023' ... --- _id: '43052' abstract: - lang: eng text: We 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 desired radiation patterns in the far-field. The OPAs are numerically optimized to have an upward efficiency of up to 90%, targeting radiation concentration mainly in the field of view. We envision that our OPAs have the ability of generating 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 last_name: Farheen - 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: https://orcid.org/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 silicon antennas for optical phased arrays. In: García-Blanco SM, Cheben P, eds. Integrated Optics: Devices, Materials, and Technologies XXVII. SPIE; 2023:124241D. doi:10.1117/12.2658716' apa: 'Farheen, H., Strauch, A., Scheytt, J. C., Myroshnychenko, V., & Förstner, J. (2023). Optimized silicon antennas for optical phased arrays. In S. M. García-Blanco & P. Cheben (Eds.), Integrated Optics: Devices, Materials, and Technologies XXVII (p. 124241D). SPIE. https://doi.org/10.1117/12.2658716' bibtex: '@inproceedings{Farheen_Strauch_Scheytt_Myroshnychenko_Förstner_2023, title={Optimized silicon antennas for optical phased arrays}, DOI={10.1117/12.2658716}, booktitle={Integrated Optics: Devices, Materials, and Technologies XXVII}, publisher={SPIE}, author={Farheen, Henna and Strauch, Andreas and Scheytt, J. Christoph and Myroshnychenko, Viktor and Förstner, Jens}, editor={García-Blanco, Sonia M. and Cheben, Pavel}, year={2023}, pages={124241D} }' chicago: 'Farheen, Henna, Andreas Strauch, J. Christoph Scheytt, Viktor Myroshnychenko, and Jens Förstner. “Optimized Silicon Antennas for Optical Phased Arrays.” In Integrated Optics: Devices, Materials, and Technologies XXVII, edited by Sonia M. García-Blanco and Pavel Cheben, 124241D. SPIE, 2023. https://doi.org/10.1117/12.2658716.' ieee: 'H. Farheen, A. Strauch, J. C. Scheytt, V. Myroshnychenko, and J. Förstner, “Optimized silicon antennas for optical phased arrays,” in Integrated Optics: Devices, Materials, and Technologies XXVII, 2023, p. 124241D, doi: 10.1117/12.2658716.' mla: 'Farheen, Henna, et al. “Optimized Silicon Antennas for Optical Phased Arrays.” Integrated Optics: Devices, Materials, and Technologies XXVII, edited by Sonia M. García-Blanco and Pavel Cheben, SPIE, 2023, p. 124241D, doi:10.1117/12.2658716.' short: 'H. Farheen, A. Strauch, J.C. Scheytt, V. Myroshnychenko, J. Förstner, in: S.M. García-Blanco, P. Cheben (Eds.), Integrated Optics: Devices, Materials, and Technologies XXVII, SPIE, 2023, p. 124241D.' date_created: 2023-03-21T12:35:18Z date_updated: 2023-03-22T20:53:50Z ddc: - '530' department: - _id: '61' - _id: '230' - _id: '429' doi: 10.1117/12.2658716 editor: - first_name: Sonia M. full_name: García-Blanco, Sonia M. last_name: García-Blanco - first_name: Pavel full_name: Cheben, Pavel last_name: Cheben file: - access_level: request content_type: application/pdf creator: fossie date_created: 2023-03-22T07:41:49Z date_updated: 2023-03-22T20:53:11Z file_id: '43055' file_name: 2023-01 Poster Photonics West Henna OPA_A0.pdf file_size: 1747396 relation: main_file file_date_updated: 2023-03-22T20:53:11Z has_accepted_license: '1' keyword: - tet_topic_opticalantenna language: - iso: eng page: '124241D ' publication: 'Integrated Optics: Devices, Materials, and Technologies XXVII' publication_status: published publisher: SPIE status: public title: Optimized silicon antennas for optical phased arrays type: conference user_id: '14931' 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 last_name: Farheen - 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: 2023-04-20T10:03:40Z 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' name: 'TRR 142: TRR 142' - _id: '55' name: 'TRR 142 - B: TRR 142 - Project Area B' - _id: '167' 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' ... --- _id: '44097' abstract: - lang: eng text: We present strong enhancement of third harmonic generation in an amorphous silicon metasurface consisting of elliptical nano resonators. We show that this enhancement originates from a new type of multi-mode Fano mechanism. These ‘Super-Fano’ resonances are investigated numerically in great detail using full-wave simulations. The theoretically predicted behavior of the metasurface is experimentally verified by linear and nonlinear transmission spectroscopy. Moreover, quantitative nonlinear measurements are performed, in which an absolute conversion efficiency as high as ηmax ≈ 2.8 × 10−7 a peak power intensity of 1.2 GW cm−2 is found. Compared to an unpatterned silicon film of the same thickness amplification factors of up to ~900 are demonstrated. Our results pave the way to exploiting a strong Fano-type multi-mode coupling in metasurfaces for high THG in potential applications. article_type: original author: - first_name: David full_name: Hähnel, David last_name: Hähnel - first_name: Christian full_name: Golla, Christian last_name: Golla - first_name: Maximilian full_name: Albert, Maximilian last_name: Albert - first_name: Thomas full_name: Zentgraf, Thomas id: '30525' last_name: Zentgraf orcid: 0000-0002-8662-1101 - 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 - first_name: Cedrik full_name: Meier, Cedrik id: '20798' last_name: Meier orcid: https://orcid.org/0000-0002-3787-3572 citation: ama: 'Hähnel D, Golla C, Albert M, et al. A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces. Light: Science & Applications. 2023;12(1):97. doi:https://doi.org/10.1038/s41377-023-01134-1' apa: 'Hähnel, D., Golla, C., Albert, M., Zentgraf, T., Myroshnychenko, V., Förstner, J., & Meier, C. (2023). A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces. Light: Science & Applications, 12(1), 97. https://doi.org/10.1038/s41377-023-01134-1' bibtex: '@article{Hähnel_Golla_Albert_Zentgraf_Myroshnychenko_Förstner_Meier_2023, title={A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces}, volume={12}, DOI={https://doi.org/10.1038/s41377-023-01134-1}, number={1}, journal={Light: Science & Applications}, publisher={Springer Nature}, author={Hähnel, David and Golla, Christian and Albert, Maximilian and Zentgraf, Thomas and Myroshnychenko, Viktor and Förstner, Jens and Meier, Cedrik}, year={2023}, pages={97} }' chicago: 'Hähnel, David, Christian Golla, Maximilian Albert, Thomas Zentgraf, Viktor Myroshnychenko, Jens Förstner, and Cedrik Meier. “A Multi-Mode Super-Fano Mechanism for Enhanced Third Harmonic Generation in Silicon Metasurfaces.” Light: Science & Applications 12, no. 1 (2023): 97. https://doi.org/10.1038/s41377-023-01134-1.' ieee: 'D. Hähnel et al., “A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces,” Light: Science & Applications, vol. 12, no. 1, p. 97, 2023, doi: https://doi.org/10.1038/s41377-023-01134-1.' mla: 'Hähnel, David, et al. “A Multi-Mode Super-Fano Mechanism for Enhanced Third Harmonic Generation in Silicon Metasurfaces.” Light: Science & Applications, vol. 12, no. 1, Springer Nature, 2023, p. 97, doi:https://doi.org/10.1038/s41377-023-01134-1.' short: 'D. Hähnel, C. Golla, M. Albert, T. Zentgraf, V. Myroshnychenko, J. Förstner, C. Meier, Light: Science & Applications 12 (2023) 97.' date_created: 2023-04-21T09:45:07Z date_updated: 2023-04-21T10:04:05Z ddc: - '530' department: - _id: '61' - _id: '230' - _id: '429' doi: https://doi.org/10.1038/s41377-023-01134-1 file: - access_level: open_access content_type: application/pdf creator: fossie date_created: 2023-04-21T10:00:27Z date_updated: 2023-04-21T10:00:27Z file_id: '44098' file_name: 2023-04 Hähnel - LSA - Multimode Fano THG.pdf file_size: 2088874 relation: main_file - access_level: open_access content_type: application/pdf creator: fossie date_created: 2023-04-21T10:03:30Z date_updated: 2023-04-21T10:03:30Z file_id: '44099' file_name: 2023-04 Hähnel - LSA - Multimode Fano THG (supplementary information).pdf file_size: 986743 relation: supplementary_material file_date_updated: 2023-04-21T10:03:30Z has_accepted_license: '1' intvolume: ' 12' issue: '1' keyword: - tet_topic_meta language: - iso: eng oa: '1' page: '97' publication: 'Light: Science & Applications' publication_identifier: issn: - 2047-7538 publication_status: published publisher: Springer Nature quality_controlled: '1' status: public title: A multi-mode super-fano mechanism for enhanced third harmonic generation in silicon metasurfaces type: journal_article user_id: '158' volume: 12 year: '2023' ... --- _id: '45596' abstract: - lang: eng text: Dielectric metasurfaces provide a unique platform for efficient harmonic generation and optical wavefront manipulation at the nanoscale. Tailoring phase and amplitude of a nonlinearly generated wave with a high emission efficiency using resonance-based metasurfaces is a challenging task that often requires state-of-the-art numerical methods. Here, we propose a simple yet effective approach combining a sampling method with a Monte Carlo approach to design the third-harmonic wavefront generated by all-dielectric metasurfaces composed of elliptical silicon nanodisks. Using this approach, we theoretically demonstrate the full nonlinear 2π phase control with a uniform and highest possible amplitude in the considered parameter space, allowing us to design metasurfaces operating as third harmonic beam deflectors capable of steering light into a desired direction with high emission efficiency. The TH beam deflection with a record calculated average conversion efficiency of 1.2 × 10–1 W–2 is achieved. We anticipate that the proposed approach will be widely applied as alternative to commonly used optimization algorithms with higher complexity and implementation effort for the design of metasurfaces with other holographic functionalities. author: - first_name: David full_name: Hähnel, David last_name: Hähnel - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 - first_name: Viktor full_name: Myroshnychenko, Viktor id: '46371' last_name: Myroshnychenko citation: ama: Hähnel D, Förstner J, Myroshnychenko V. Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces. ACS Photonics. Published online 2023. doi:10.1021/acsphotonics.2c01967 apa: Hähnel, D., Förstner, J., & Myroshnychenko, V. (2023). Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces. ACS Photonics. https://doi.org/10.1021/acsphotonics.2c01967 bibtex: '@article{Hähnel_Förstner_Myroshnychenko_2023, title={Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces}, DOI={10.1021/acsphotonics.2c01967}, journal={ACS Photonics}, publisher={American Chemical Society (ACS)}, author={Hähnel, David and Förstner, Jens and Myroshnychenko, Viktor}, year={2023} }' chicago: Hähnel, David, Jens Förstner, and Viktor Myroshnychenko. “Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces.” ACS Photonics, 2023. https://doi.org/10.1021/acsphotonics.2c01967. ieee: 'D. Hähnel, J. Förstner, and V. Myroshnychenko, “Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces,” ACS Photonics, 2023, doi: 10.1021/acsphotonics.2c01967.' mla: Hähnel, David, et al. “Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces.” ACS Photonics, American Chemical Society (ACS), 2023, doi:10.1021/acsphotonics.2c01967. short: D. Hähnel, J. Förstner, V. Myroshnychenko, ACS Photonics (2023). date_created: 2023-06-13T09:43:25Z date_updated: 2023-06-13T09:49:12Z ddc: - '530' department: - _id: '61' - _id: '230' - _id: '429' doi: 10.1021/acsphotonics.2c01967 file: - access_level: open_access content_type: application/pdf creator: fossie date_created: 2023-06-13T09:48:17Z date_updated: 2023-06-13T09:48:17Z file_id: '45597' file_name: 2023-06 Hähnel - ACS Photonics - Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces.pdf file_size: 5382111 relation: main_file file_date_updated: 2023-06-13T09:48:17Z has_accepted_license: '1' keyword: - tet_topic_meta language: - iso: eng main_file_link: - open_access: '1' oa: '1' project: - _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: '53' grant_number: '231447078' name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten zu funktionellen Strukturen' - _id: '75' grant_number: '231447078' name: 'TRR 142 - C05: TRR 142 - Nichtlineare optische Oberflächen basierend auf ZnO-plasmonischen Hybrid-Nanostrukturen (C05)' - _id: '56' name: 'TRR 142 - C: TRR 142 - Project Area C' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: ACS Photonics publication_identifier: issn: - 2330-4022 - 2330-4022 publication_status: published publisher: American Chemical Society (ACS) status: public title: Efficient Modeling and Tailoring of Nonlinear Wavefronts in Dielectric Metasurfaces type: journal_article user_id: '158' 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 last_name: Farheen - 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: 2023-12-21T09:48:39Z 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: '49890' abstract: - lang: eng text: In this paper, the influence of the environment on an inductive location system is analyzed. In the inductive location method, high frequency magnetic fields generated by planar coils lead to induction in other coils, which is used for localization analysis. Magnetic fields are not affected by changes in the dielectric properties of the environment, which is an advantage over other localization methods. However, electrical material parameters can still affect the localization results by indirect effects. For this reason, in this publication the influence will be investigated using real material parameters and their effects on the localization will be considered, so that the robustness and the limits of the inductive localization can be evaluated. author: - first_name: Sven full_name: Lange, Sven id: '38240' last_name: Lange - first_name: Ulrich full_name: Hilleringmann, Ulrich id: '20179' last_name: Hilleringmann - first_name: Christian full_name: Hedayat, Christian last_name: Hedayat - first_name: Harald full_name: Kuhn, Harald last_name: Kuhn - first_name: Jens full_name: Förstner, Jens id: '158' last_name: Förstner orcid: 0000-0001-7059-9862 citation: ama: 'Lange S, Hilleringmann U, Hedayat C, Kuhn H, Förstner J. Characterization of Various Environmental Influences on the Inductive Localization. In: 2023 IEEE Conference on Antenna Measurements and Applications (CAMA). IEEE; 2023. doi:10.1109/cama57522.2023.10352780' apa: Lange, S., Hilleringmann, U., Hedayat, C., Kuhn, H., & Förstner, J. (2023). Characterization of Various Environmental Influences on the Inductive Localization. 2023 IEEE Conference on Antenna Measurements and Applications (CAMA). 2023 IEEE Conference on Antenna Measurements and Applications (CAMA), Genoa, Italy . https://doi.org/10.1109/cama57522.2023.10352780 bibtex: '@inproceedings{Lange_Hilleringmann_Hedayat_Kuhn_Förstner_2023, place={Genoa, Italy }, title={Characterization of Various Environmental Influences on the Inductive Localization}, DOI={10.1109/cama57522.2023.10352780}, booktitle={2023 IEEE Conference on Antenna Measurements and Applications (CAMA)}, publisher={IEEE}, author={Lange, Sven and Hilleringmann, Ulrich and Hedayat, Christian and Kuhn, Harald and Förstner, Jens}, year={2023} }' chicago: 'Lange, Sven, Ulrich Hilleringmann, Christian Hedayat, Harald Kuhn, and Jens Förstner. “Characterization of Various Environmental Influences on the Inductive Localization.” In 2023 IEEE Conference on Antenna Measurements and Applications (CAMA). Genoa, Italy : IEEE, 2023. https://doi.org/10.1109/cama57522.2023.10352780.' ieee: 'S. Lange, U. Hilleringmann, C. Hedayat, H. Kuhn, and J. Förstner, “Characterization of Various Environmental Influences on the Inductive Localization,” presented at the 2023 IEEE Conference on Antenna Measurements and Applications (CAMA), Genoa, Italy , 2023, doi: 10.1109/cama57522.2023.10352780.' mla: Lange, Sven, et al. “Characterization of Various Environmental Influences on the Inductive Localization.” 2023 IEEE Conference on Antenna Measurements and Applications (CAMA), IEEE, 2023, doi:10.1109/cama57522.2023.10352780. short: 'S. Lange, U. Hilleringmann, C. Hedayat, H. Kuhn, J. Förstner, in: 2023 IEEE Conference on Antenna Measurements and Applications (CAMA), IEEE, Genoa, Italy , 2023.' conference: end_date: 2023-11-17 location: 'Genoa, Italy ' name: 2023 IEEE Conference on Antenna Measurements and Applications (CAMA) start_date: 2023-11-15 date_created: 2023-12-20T08:36:58Z date_updated: 2023-12-21T09:51:11Z department: - _id: '59' - _id: '61' - _id: '485' doi: 10.1109/cama57522.2023.10352780 keyword: - Planar coils - inductive locating - magnetic fields - environmental influences - eddy currents - tet_topic_hf language: - iso: eng main_file_link: - url: https://ieeexplore.ieee.org/document/10352780 place: 'Genoa, Italy ' publication: 2023 IEEE Conference on Antenna Measurements and Applications (CAMA) publication_identifier: eisbn: - 979-8-3503-2304-7 publication_status: published publisher: IEEE status: public title: Characterization of Various Environmental Influences on the Inductive Localization type: conference user_id: '158' year: '2023' ... --- _id: '48599' abstract: - lang: eng text: AbstractThe biexciton‐exciton emission cascade commonly used in quantum‐dot systems to generate polarization entanglement yields photons with intrinsically limited indistinguishability. In the present work, it focuses on the generation of pairs of photons with high degrees of polarization entanglement and simultaneously high indistinguishability. It achieves this goal by selectively reducing the biexciton lifetime with an optical resonator. It demonstrates 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 twofold degenerate optical modes. The 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. It reports non‐trivial dependencies on system parameters and use the predictive power of the combined theoretical approach to determine the optimal range of Purcell enhancement that maximizes indistinguishability and entanglement to near unity values, here specifically for the telecom C‐band at 1550 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 Using Tailored Cavity Designs. Advanced Quantum Technologies. Published online 2023. doi:10.1002/qute.202300142 apa: Bauch, D., Siebert, D., Jöns, K., Förstner, J., & Schumacher, S. (2023). On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs. Advanced Quantum Technologies. https://doi.org/10.1002/qute.202300142 bibtex: '@article{Bauch_Siebert_Jöns_Förstner_Schumacher_2023, title={On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs}, DOI={10.1002/qute.202300142}, journal={Advanced Quantum Technologies}, publisher={Wiley}, 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 Using Tailored Cavity Designs.” Advanced Quantum Technologies, 2023. https://doi.org/10.1002/qute.202300142. ieee: 'D. Bauch, D. Siebert, K. Jöns, J. Förstner, and S. Schumacher, “On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs,” Advanced Quantum Technologies, 2023, doi: 10.1002/qute.202300142.' mla: Bauch, David, et al. “On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs.” Advanced Quantum Technologies, Wiley, 2023, doi:10.1002/qute.202300142. short: D. Bauch, D. Siebert, K. Jöns, J. Förstner, S. Schumacher, Advanced Quantum Technologies (2023). date_created: 2023-11-03T10:07:38Z date_updated: 2023-12-21T10:41:17Z department: - _id: '61' - _id: '230' - _id: '429' - _id: '623' doi: 10.1002/qute.202300142 keyword: - tet_topic_qd language: - iso: eng main_file_link: - open_access: '1' url: https://onlinelibrary.wiley.com/doi/10.1002/qute.202300142 oa: '1' project: - _id: '173' grant_number: '231447078' name: 'TRR 142 - C09: TRR 142 - Ideale Erzeugung von Photonenpaaren für Verschränkungsaustausch bei Telekom Wellenlängen (C09*)' - _id: '167' grant_number: '231447078' name: 'TRR 142 - B06: TRR 142 - Ultraschnelle kohärente opto-elektronische Kontrolle eines photonischen Quantensystems (B06*)' - _id: '52' name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing' publication: Advanced Quantum Technologies publication_identifier: issn: - 2511-9044 - 2511-9044 publication_status: published publisher: Wiley related_material: record: - id: '43246' relation: earlier_version status: public status: public title: On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs type: journal_article user_id: '158' year: '2023' ...