@inbook{47543,
  author       = {{Zentgraf, Thomas and Sain, Basudeb and Zhang, Shuang}},
  booktitle    = {{Fundamentals and Applications of Nonlinear Nanophotonics}},
  editor       = {{Panoiu, Nicoae C.}},
  isbn         = {{978-0-323-90614-2}},
  publisher    = {{Elsevier}},
  title        = {{{Symmetry governed nonlinear selection rules in nanophotonics }}},
  doi          = {{10.1016/B978-0-323-90614-2.00011-0}},
  year         = {{2023}},
}

@inproceedings{43051,
  abstract     = {{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       = {{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 Linden, Stefan and Myroshnychenko, Viktor and Förstner, Jens}},
  booktitle    = {{Integrated Optics: Devices, Materials, and Technologies XXVII}},
  editor       = {{García-Blanco, Sonia M. and Cheben, Pavel}},
  keywords     = {{tet_topic_opticalantenna}},
  pages        = {{124241E}},
  publisher    = {{SPIE}},
  title        = {{{Tailoring the directive nature of optical waveguide antennas}}},
  doi          = {{10.1117/12.2658921}},
  year         = {{2023}},
}

@article{40513,
  abstract     = {{Geometric-phase dielectric meta-lenses made of silicon with high numerical aperture and short focal lengths are fabricated and characterised. For circularly polarised light, the same meta-lens can act as a converging or diverging lens, depending on the handedness of the circular polarisation. This effect enables application for optical tweezers that trap or release µm-size polymer beads floating in a microfluidic channel on demand. An electrically addressable polarisation converter based on liquid crystals may be used to switch between the two states of polarisation, at which the light transmitted through the meta-lens is focused (trapping) or defocussed (releasing), respectively.}},
  author       = {{Geromel, René and Rennerich, Roman and Zentgraf, Thomas and Kitzerow, Heinz-Siegfried}},
  journal      = {{Liquid Crystals}},
  number       = {{7-10}},
  pages        = {{1193--1203}},
  publisher    = {{Taylor & Francis}},
  title        = {{{Geometric-phase metalens to be used for tunable optical tweezers in microfluidics}}},
  doi          = {{10.1080/02678292.2023.2171146}},
  volume       = {{50}},
  year         = {{2023}},
}

@article{55900,
  author       = {{Scharwald, Dennis and Meier, Torsten and Sharapova, Polina}},
  issn         = {{2643-1564}},
  journal      = {{Physical Review Research}},
  number       = {{4}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Phase sensitivity of spatially broadband high-gain SU(1,1) interferometers}}},
  doi          = {{10.1103/physrevresearch.5.043158}},
  volume       = {{5}},
  year         = {{2023}},
}

@article{31059,
  abstract     = {{In this article we prove meromorphic continuation of weighted zeta functions in the framework of open hyperbolic systems by using the meromorphically continued restricted resolvent of Dyatlov and Guillarmou (2016). We obtain a residue formula proving equality between residues of weighted zetas and invariant Ruelle distributions. We combine this equality with results of Guillarmou, Hilgert and Weich (2021) in order to relate the residues to Patterson-Sullivan distributions. Finally we provide proof-of-principle results concerning the numerical calculation of invariant Ruelle distributions for 3-disc scattering systems.}},
  author       = {{Schütte, Philipp and Weich, Tobias and Barkhofen, Sonja}},
  journal      = {{Communications in Mathematical Physics}},
  pages        = {{655--678}},
  title        = {{{Meromorphic Continuation of Weighted Zeta Functions on Open Hyperbolic Systems}}},
  doi          = {{https://doi.org/10.1007/s00220-022-04538-z}},
  volume       = {{398}},
  year         = {{2023}},
}

@article{61252,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>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, 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.</jats:p>}},
  author       = {{Bauch, David and Siebert, Dustin and Jöns, Klaus D. and Förstner, Jens and Schumacher, Stefan}},
  issn         = {{2511-9044}},
  journal      = {{Advanced Quantum Technologies}},
  number       = {{1}},
  publisher    = {{Wiley}},
  title        = {{{On‐Demand Indistinguishable and Entangled Photons Using Tailored Cavity Designs}}},
  doi          = {{10.1002/qute.202300142}},
  volume       = {{7}},
  year         = {{2023}},
}

@article{61266,
  abstract     = {{<jats:p>This review examines the use of continuous-variable spectroscopy techniques for investigating quantum coherence and light-matter interactions in semiconductor systems with ultrafast dynamics. Special emphasis is placed on multichannel homodyne detection as a powerful tool to measure the quantum coherence and the full density matrix of a polariton system. Observations, such as coherence times that exceed the nanosecond scale obtained by monitoring the temporal decay of quantum coherence in a polariton condensate, are discussed. Proof-of-concept experiments and numerical simulations that demonstrate the enhanced resourcefulness of the produced system states for modern quantum protocols are assessed. The combination of tailored resource quantifiers and ultrafast spectroscopy techniques that have recently been demonstrated paves the way for future applications of quantum information technologies.</jats:p>}},
  author       = {{Lüders, Carolin and Barkhausen, Franziska and Pukrop, Matthias and Rozas, Elena and Sperling, Jan and Schumacher, Stefan and Aßmann, Marc}},
  issn         = {{2159-3930}},
  journal      = {{Optical Materials Express}},
  number       = {{11}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Continuous-variable quantum optics and resource theory for ultrafast semiconductor spectroscopy [Invited]}}},
  doi          = {{10.1364/ome.497006}},
  volume       = {{13}},
  year         = {{2023}},
}

@article{38541,
  author       = {{Barkhofen, Sonja and Brecht, Benjamin and Silberhorn, Christine}},
  journal      = {{Physik in unserer Zeit}},
  number       = {{1}},
  pages        = {{10--11}},
  publisher    = {{Wiley}},
  title        = {{{Verschränkung wie am Fließband}}},
  doi          = {{https://doi.org/10.1002/piuz.202370107}},
  volume       = {{54}},
  year         = {{2023}},
}

@article{36471,
  abstract     = {{<jats:p>Superconducting nanowire single-photon detectors (SNSPDs) show near unity efficiency, low dark count rate, and short recovery time. Combining these characteristics with temporal control of SNSPDs broadens their applications as in active de-latching for higher dynamic range counting or temporal filtering for pump-probe spectroscopy or LiDAR. To that end, we demonstrate active gating of an SNSPD with a minimum off-to-on rise time of 2.4 ns and a total gate length of 5.0 ns. We show how the rise time depends on the inductance of the detector in combination with the control electronics. The gate window is demonstrated to be fully and freely, electrically tunable up to 500 ns at a repetition rate of 1.0 MHz, as well as ungated, free-running operation. Control electronics to generate the gating are mounted on the 2.3 K stage of a closed-cycle sorption cryostat, while the detector is operated on the cold stage at 0.8 K. We show that the efficiency and timing jitter of the detector is not altered during the on-time of the gating window. We exploit gated operation to demonstrate a method to increase in the photon counting dynamic range by a factor 11.2, as well as temporal filtering of a strong pump in an emulated pump-probe experiment.</jats:p>}},
  author       = {{Hummel, Thomas and Widhalm, Alex and Höpker, Jan Philipp and Jöns, Klaus and Chang, Jin and Fognini, Andreas and Steinhauer, Stephan and Zwiller, Val and Zrenner, Artur and Bartley, Tim}},
  issn         = {{1094-4087}},
  journal      = {{Optics Express}},
  keywords     = {{Atomic and Molecular Physics, and Optics}},
  number       = {{1}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Nanosecond gating of superconducting nanowire single-photon detectors using cryogenic bias circuitry}}},
  doi          = {{10.1364/oe.472058}},
  volume       = {{31}},
  year         = {{2023}},
}

@article{63043,
  abstract     = {{Spatial modes of light have become highly attractive to increase the dimension and, thereby, security and information capacity in quantum key distribution (QKD). So far, only transverse electric field components have been considered, while longitudinal polarization components have remained neglected. Here, we present an approach to include all three spatial dimensions of electric field oscillation in QKD by implementing our tunable, on-a-chip vector beam decoder (VBD). This inversely designed device pioneers the "preparation" and "measurement" of three-dimensionally polarized mutually unbiased basis states for high-dimensional (HD) QKD and paves the way for the integration of HD QKD with spatial modes in multifunctional on-a-chip photonics platforms.}},
  title        = {{{Tunable vector beam decoder by inverse design for high-dimensional quantum key distribution with 3D polarized spatial modes}}},
  doi          = {{10.48550/ARXIV.2304.12296}},
  year         = {{2023}},
}

@inproceedings{45578,
  abstract     = {{A frequency-flexible Nyquist pulse synthesizer is presented with optical pulse bandwidths up to fopt=100 GHz and repetition rates equal to fopt/9, fabricated in an electronic-photonic co-integrated platform utilizing linear on-chip drivers.}},
  author       = {{Kress, Christian and Schwabe, Tobias and Silberhorn, Christine and Scheytt, J. Christoph}},
  booktitle    = {{ Conference on Lasers and Electro-Optics (CLEO) 2023}},
  location     = {{San Jose, CA, USA}},
  publisher    = {{Optica Publishing Group}},
  title        = {{{Generation of 100 GHz Periodic Nyquist Pulses using Cascaded Mach-Zehnder Modulators in a Silicon Electronic-Photonic Platform}}},
  doi          = {{https://doi.org/10.1364/CLEO_SI.2023.SF1P.6}},
  year         = {{2023}},
}

@article{46468,
  author       = {{Lange, Nina Amelie and Schapeler, Timon and Höpker, Jan Philipp and Protte, Maximilian and Bartley, Tim}},
  issn         = {{2469-9926}},
  journal      = {{Physical Review A}},
  number       = {{2}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Degenerate photons from a cryogenic spontaneous parametric down-conversion source}}},
  doi          = {{10.1103/physreva.108.023701}},
  volume       = {{108}},
  year         = {{2023}},
}

@article{44081,
  author       = {{Serino, Laura and Gil López, Jano and Stefszky, Michael and Ricken, Raimund and Eigner, Christof and Brecht, Benjamin and Silberhorn, Christine}},
  issn         = {{2691-3399}},
  journal      = {{PRX Quantum}},
  keywords     = {{General Physics and Astronomy, Mathematical Physics, Applied Mathematics, Electronic, Optical and Magnetic Materials, Electrical and Electronic Engineering, General Computer Science}},
  number       = {{2}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Realization of a Multi-Output Quantum Pulse Gate for Decoding High-Dimensional Temporal Modes of Single-Photon States}}},
  doi          = {{10.1103/prxquantum.4.020306}},
  volume       = {{4}},
  year         = {{2023}},
}

@article{42648,
  abstract     = {{In real photonic quantum systems losses are an unavoidable factor limiting the scalability to many modes and particles, restraining their application in fields as quantum information and communication. For this reason, a considerable amount of engineering effort has been taken in order to improve the quality of particle sources and system components. At the same time, data analysis and collection methods based on post-selection have been used to mitigate the effect of particle losses. This has allowed for investigating experimentally multi-particle evolutions where the observer lacks knowledge about the system's intermediate propagation states. Nonetheless, the fundamental question how losses affect the behaviour of the surviving subset of a multi-particle system has not been investigated so far. For this reason, here we study the impact of particle losses in a quantum walk of two photons reconstructing the output probability distributions for one photon conditioned on the loss of the other in a known mode and temporal step of our evolution network. We present the underlying theoretical scheme that we have devised in order to model controlled particle losses, we describe an experimental platform capable of implementing our theory in a time multiplexing encoding. In the end we show how localized particle losses change the output distributions without altering their asymptotic spreading properties. Finally we devise a quantum civilization problem, a two walker generalisation of single particle recurrence processes.}},
  author       = {{Pegoraro, Federico and Held, Philip and Barkhofen, Sonja and Brecht, Benjamin and Silberhorn, Christine}},
  issn         = {{0031-8949}},
  journal      = {{Physica Scripta}},
  number       = {{3}},
  publisher    = {{IOP Publishing}},
  title        = {{{Dynamic conditioning of two particle discrete-time quantum walks}}},
  doi          = {{10.1088/1402-4896/acbcaa}},
  volume       = {{98}},
  year         = {{2023}},
}

@article{50271,
  author       = {{Gharibian, Sevag and Le Gall, François}},
  issn         = {{0097-5397}},
  journal      = {{SIAM Journal on Computing}},
  keywords     = {{General Mathematics, General Computer Science}},
  number       = {{4}},
  pages        = {{1009--1038}},
  publisher    = {{Society for Industrial & Applied Mathematics (SIAM)}},
  title        = {{{Dequantizing the Quantum Singular Value Transformation: Hardness and Applications to Quantum Chemistry and the Quantum PCP Conjecture}}},
  doi          = {{10.1137/22m1513721}},
  volume       = {{52}},
  year         = {{2023}},
}

@article{30195,
  abstract     = {{While plasmonic particles can provide optical resonances in a wide spectral range from the lower visible up to the near-infrared, often, symmetry effects are utilized to obtain particular optical responses. By breaking certain spatial symmetries, chiral structures arise and provide robust chiroptical responses to these plasmonic resonances. Here, we observe strong chiroptical responses in the linear and nonlinear optical regime for chiral L-handed helicoid-III nanoparticles and quantify them by means of an asymmetric factor, the so-called g-factor. We calculate the linear optical g-factors for two distinct chiroptical resonances to −0.12 and –0.43 and the nonlinear optical g-factors to −1.45 and −1.63. The results demonstrate that the chirality of the helicoid-III nanoparticles is strongly enhanced in the nonlinear regime.}},
  author       = {{Spreyer, Florian and Mun, Jungho and Kim, Hyeohn and Kim, Ryeong Myeong and Nam, Ki Tae and Rho, Junsuk and Zentgraf, Thomas}},
  issn         = {{2330-4022}},
  journal      = {{ACS Photonics}},
  keywords     = {{Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics, Biotechnology, Electronic, Optical and Magnetic Materials}},
  number       = {{3}},
  pages        = {{784–792}},
  publisher    = {{American Chemical Society (ACS)}},
  title        = {{{Second Harmonic Optical Circular Dichroism of Plasmonic Chiral Helicoid-III Nanoparticles}}},
  doi          = {{10.1021/acsphotonics.1c00882}},
  volume       = {{9}},
  year         = {{2022}},
}

@article{29902,
  author       = {{Reineke Matsudo, Bernhard and Sain, Basudeb and Carletti, Luca and Zhang, Xue and Gao, Wenlong and Angelis, Costantino and Huang, Lingling and Zentgraf, Thomas}},
  issn         = {{2198-3844}},
  journal      = {{Advanced Science}},
  keywords     = {{General Physics and Astronomy, General Engineering, Biochemistry, Genetics and Molecular Biology (miscellaneous), General Materials Science, General Chemical Engineering, Medicine (miscellaneous)}},
  number       = {{12}},
  publisher    = {{Wiley}},
  title        = {{{Efficient Frequency Conversion with Geometric Phase Control in Optical Metasurfaces}}},
  doi          = {{10.1002/advs.202104508}},
  volume       = {{9}},
  year         = {{2022}},
}

@article{30964,
  author       = {{Gao, Wenlong and Sain, Basudeb and Zentgraf, Thomas}},
  issn         = {{2331-7019}},
  journal      = {{Physical Review Applied}},
  keywords     = {{General Physics and Astronomy}},
  number       = {{4}},
  publisher    = {{American Physical Society (APS)}},
  title        = {{{Spin-Orbit Interaction of Light Enabled by Negative Coupling in High-Quality-Factor Optical Metasurfaces}}},
  doi          = {{10.1103/physrevapplied.17.044022}},
  volume       = {{17}},
  year         = {{2022}},
}

@inproceedings{34465,
  author       = {{laeim, Huddad and Schlickriede, Christian and Chaisakul, Papichaya and Chattham, Nattaporn and Panitchakan, Hathai and Siangchaew, Krisda and Zentgraf, Thomas and Pattanaporhratana, Apichart}},
  booktitle    = {{Metamaterials, Metadevices, and Metasystems 2022}},
  editor       = {{Engheta, Nader and Noginov, Mikhail A. and Zheludev, Nikolay I.}},
  publisher    = {{SPIE}},
  title        = {{{Design and investigation of a metalens for efficiency enhancement of laser-waveguide coupling in a limited space system}}},
  doi          = {{10.1117/12.2629789}},
  year         = {{2022}},
}

@article{31480,
  abstract     = {{Optical geometric phase encoded by in-plane spatial orientation of microstructures has promoted the rapid development of numerous functional meta-devices. However, pushing the concept of the geometric phase toward the acoustic community still faces challenges. In this work, we utilize two acoustic nonlocal metagratings that could support a direct conversion between an acoustic plane wave and a designated vortex mode to obtain the acoustic geometric phase, in which an orbital angular momentum conversion process plays a vital role. In addition, we realize the acoustic geometric phases of different orders by merely varying the orientation angle of the acoustic nonlocal metagratings. Intriguingly, according to our developed theory, we reveal that the reflective acoustic geometric phase, which is twice the transmissive one, can be readily realized by transferring the transmitted configuration to a reflected one. Both the theoretical study and experimental measurements verify the announced transmissive and reflective acoustic geometric phases. Moreover, the reconfigurability and continuous phase modulation that covers the 2π range shown by the acoustic geometric phases provide us with the alternatives in advanced acoustic wavefront control.}},
  author       = {{Liu, Bingyi and Zhou, Zhiling and Wang, Yongtian and Zentgraf, Thomas and Li, Yong and Huang, Lingling}},
  issn         = {{0003-6951}},
  journal      = {{Applied Physics Letters}},
  keywords     = {{Physics and Astronomy (miscellaneous)}},
  number       = {{21}},
  publisher    = {{AIP Publishing}},
  title        = {{{Experimental verification of the acoustic geometric phase}}},
  doi          = {{10.1063/5.0091474}},
  volume       = {{120}},
  year         = {{2022}},
}