@article{51156, abstract = {{Ferroelectric domain wall (DW) conductivity (DWC) can be attributed to two separate mechanisms: (a) the injection/ejection of charge carriers across the Schottky barrier formed at the (metal-)electrode-DW junction and (b) the transport of those charge carriers along the DW. Current-voltage (I-U) characteristics, recorded at variable temperatures from LiNbO3 (LNO) DWs, are clearly able to differentiate between these two contributions. Practically, they allow us to directly quantify the physical parameters relevant to the two mechanisms (a) and (b) mentioned above. These are, for example, the resistance of the DW, the saturation current, the ideality factor, and the Schottky barrier height of the electrode-DW junction. Furthermore, the activation energies needed to initiate the thermally activated electronic transport along the DWs can be extracted. In addition, we show that electronic transport along LNO DWs can be elegantly viewed and interpreted in an adapted semiconductor picture based on a double-diode, double-resistor equivalent-circuit model, the R2D2 model. Finally, our R2D2 model was checked for its universality by successfully fitting the I-U curves of not only z-cut LNO bulk DWs, but equally of z-cut thin-film LNO DWs, and of x-cut thin-film DWs as reported in literature.}}, author = {{Zahn, Manuel and Beyreuther, Elke and Kiseleva, Iuliia and Lotfy, Ahmed Samir and McCluskey, Conor J. and Maguire, Jesi R. and Suna, Ahmet and Rüsing, Michael and Gregg, J. Marty and Eng, Lukas M.}}, issn = {{2331-7019}}, journal = {{Physical Review Applied}}, keywords = {{General Physics and Astronomy}}, number = {{2}}, publisher = {{American Physical Society (APS)}}, title = {{{Equivalent-circuit model that quantitatively describes domain-wall conductivity in ferroelectric lithium }}}, doi = {{10.1103/physrevapplied.21.024007}}, volume = {{21}}, year = {{2024}}, } @article{51339, author = {{Babai-Hemati, Jonas and vom Bruch, Felix and Herrmann, Harald and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, publisher = {{Optica Publishing Group}}, title = {{{Tailored second harmonic generation inTi-diffused PPLN waveguides usingmicro-heaters}}}, doi = {{10.1364/oe.510319}}, year = {{2024}}, } @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{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{45485, author = {{Kruse, Stephan and Serino, Laura and Folge, Patrick Fabian and Echeverria Oviedo, Dana and Bhattacharjee, Abhinandan and Stefszky, Michael and Scheytt, J. Christoph and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{1041-1135}}, journal = {{IEEE Photonics Technology Letters}}, keywords = {{Electrical and Electronic Engineering, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}}, number = {{14}}, pages = {{769--772}}, publisher = {{Institute of Electrical and Electronics Engineers (IEEE)}}, title = {{{A Pulsed Lidar System With Ultimate Quantum Range Accuracy}}}, doi = {{10.1109/lpt.2023.3277515}}, volume = {{35}}, year = {{2023}}, } @article{45850, abstract = {{Interference between single photons is key for many quantum optics experiments and applications in quantum technologies, such as quantum communication or computation. It is advantageous to operate the systems at telecommunication wavelengths and to integrate the setups for these applications in order to improve stability, compactness and scalability. A new promising material platform for integrated quantum optics is lithium niobate on insulator (LNOI). Here, we realise Hong-Ou-Mandel (HOM) interference between telecom photons from an engineered parametric down-conversion source in an LNOI directional coupler. The coupler has been designed and fabricated in house and provides close to perfect balanced beam splitting. We obtain a raw HOM visibility of (93.5 ± 0.7) %, limited mainly by the source performance and in good agreement with off-chip measurements. This lays the foundation for more sophisticated quantum experiments in LNOI.}}, author = {{Babel, Silia and Bollmers, Laura and Massaro, Marcello and Luo, Kai Hong and Stefszky, Michael and Pegoraro, Federico and Held, Philip and Herrmann, Harald and Eigner, Christof and Brecht, Benjamin and Padberg, Laura and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{14}}, publisher = {{Optica Publishing Group}}, title = {{{Demonstration of Hong-Ou-Mandel interference in an LNOI directional coupler}}}, doi = {{10.1364/oe.484126}}, volume = {{31}}, year = {{2023}}, } @article{46138, abstract = {{This work reports a fully guided setup for single-mode squeezing on integrated titanium-indiffused periodically poled nonlinear resonators. A continuous-wave laser beam is delivered and the squeezed field is collected by single-mode fibers; up to −3.17(9) dB of useful squeezing is available in fibers. To showcase the usefulness of such a fiber-coupled device, we applied the generated squeezed light in a fiber-based phase sensing experiment, showing a quantum enhancement in the signal-to-noise ratio of 0.35 dB. Moreover, our investigation of the effect of photorefraction on the cavity resonance condition suggests that it causes system instabilities at high powers.}}, author = {{Domeneguetti, Renato and Stefszky, Michael and Herrmann, Harald and Silberhorn, Christine and Andersen, Ulrik L. and Neergaard-Nielsen, Jonas S. and Gehring, Tobias}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{11}}, publisher = {{Optica Publishing Group}}, title = {{{Fully guided and phase locked Ti:PPLN waveguide squeezing for applications in quantum sensing}}}, doi = {{10.1364/ol.486654}}, volume = {{48}}, year = {{2023}}, } @article{48349, abstract = {{We report a titanium indiffused waveguide resonator featuring an integrated electro-optic modulator for cavity length stabilisation that produces close to 5 dB of squeezed light at 1550 nm (2.4 dB directly measured). The resonator is locked on resonance for tens of minutes with 70 mW of SH light incident on the cavity, demonstrating that photorefraction can be mitigated. Squeezed light production concurrent with cavity length stabilisation utilising the integrated EOM is demonstrated. The device demonstrates the suitability of this platform for squeezed light generation in network applications, where stabilisation to the reference field is typically necessary.}}, author = {{Stefszky, M. and vom Bruch, F. and Santandrea, M. and Ricken, R. and Quiring, V. and Eigner, C. and Herrmann, H and Silberhorn, C}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{21}}, publisher = {{Optica Publishing Group}}, title = {{{Lithium niobate waveguide squeezer with integrated cavity length stabilisation for network applications}}}, doi = {{10.1364/oe.498423}}, volume = {{31}}, year = {{2023}}, } @article{40273, author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Dhand, Ish and Eigner, Christof and Quiring, Viktor and Barkhofen, Sonja and Brecht, Benjamin and Plenio, Martin B. and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{15}}, publisher = {{American Physical Society (APS)}}, title = {{{Scalable Generation of Multiphoton Entangled States by Active Feed-Forward and Multiplexing}}}, doi = {{10.1103/physrevlett.129.150501}}, volume = {{129}}, year = {{2022}}, } @inproceedings{43744, abstract = {{We demonstrate theoretically and experimentally complex correlations in the photon numbers of two-mode quantum states using measurement-induced nonlinearity. For this, we combine the interference of coherent states and single photons with photon sub-traction.}}, author = {{Meier, Torsten and Hoepker, Jan Philipp and Protte, Maximilian and Eigner, Christof and Silberhorn, Christine and Sharapova, Polina R. and Sperling, Jan and Bartley, Tim}}, booktitle = {{Conference on Lasers and Electro-Optics: Applications and Technology}}, isbn = {{978-1-957171-05-0}}, location = {{San Jose, California United States}}, pages = {{JTu3A. 17}}, publisher = {{Optica Publishing Group}}, title = {{{Two-Mode Photon-Number Correlations Created by Measurement-Induced Nonlinearity}}}, doi = {{10.1364/CLEO_AT.2022.JTu3A.17}}, year = {{2022}}, } @article{33484, abstract = {{We study the DC conductivity in potassium titanyl phosphate (KTiOPO4, KTP) and its isomorphs KTiOAsO4 (KTA) and Rb1%K99%TiOPO4 (RKTP) and introduce a method by which to reduce the overall ionic conductivity in KTP by a potassium nitrate treatment. Furthermore, we create so-called gray tracking in KTP and investigate the ionic conductivity in theses areas. A local unintended reduction of the ionic conductivity is observed in the gray-tracked regions, which also induce additional optical absorption in the material. We show that a thermal treatment in an oxygen-rich atmosphere removes the gray tracking and brings the ionic conductivity as well as the optical transmission back to the original level. These studies can help to choose the best material and treatment for specific applications.}}, author = {{Padberg, Laura and Quiring, Viktor and Bocchini, Adriana and Santandrea, Matteo and Gerstmann, Uwe and Schmidt, Wolf Gero and Silberhorn, Christine and Eigner, Christof}}, issn = {{2073-4352}}, journal = {{Crystals}}, pages = {{1359}}, title = {{{DC Ionic Conductivity in KTP and Its Isomorphs: Properties, Methods for Suppression, and Its Connection to Gray Tracking}}}, doi = {{10.3390/cryst12101359}}, volume = {{12}}, year = {{2022}}, } @article{34884, author = {{Prasannan, Nidhin and Sperling, Jan and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{26}}, publisher = {{American Physical Society (APS)}}, title = {{{Direct Measurement of Higher-Order Nonlinear Polarization Squeezing}}}, doi = {{10.1103/physrevlett.129.263601}}, volume = {{129}}, year = {{2022}}, } @article{30921, abstract = {{Quantum walks function as essential means to implement quantum simulators, allowing one to study complex and often directly inaccessible quantum processes in controllable systems. In this contribution, the notion of a driven Gaussian quantum walk is introduced. In contrast to typically considered quantum walks in optical settings, we describe the operation of the walk in terms of a nonlinear map rather than a unitary operation, e.g., by replacing a beam-splitter-type coin with a two-mode squeezer, being a process that is controlled and driven by a pump field. This opens previously unattainable possibilities for quantum walks that include nonlinear elements as core components of their operation, vastly extending their range of applications. A full framework for driven Gaussian quantum walks is developed, including methods to dynamically characterize nonlinear, quantum, and quantum-nonlinear effects. Moreover, driven Gaussian quantum walks are compared with their classically interfering and linear counterparts, which are based on classical coherence of light rather than quantum superpositions. In particular, the generation and boost of highly multimode entanglement, squeezing, and other quantum effects are studied over the duration of the nonlinear walk. Importantly, we prove the quantumness of the evolution itself, regardless of the input state. A scheme for an experimental realization is proposed. Furthermore, nonlinear properties of driven Gaussian quantum walks are explored, such as amplification that leads to an ever increasing number of correlated quantum particles, constituting a source of new walkers during the walk. Therefore, a concept for quantum walks is proposed that leads to—and even produces—directly accessible quantum phenomena, and that renders the quantum simulation of nonlinear processes possible.}}, author = {{Held, Philip and Engelkemeier, Melanie and De, Syamsundar and Barkhofen, Sonja and Sperling, Jan and Silberhorn, Christine}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{4}}, publisher = {{American Physical Society (APS)}}, title = {{{Driven Gaussian quantum walks}}}, doi = {{10.1103/physreva.105.042210}}, volume = {{105}}, year = {{2022}}, } @article{26218, author = {{Santandrea, Matteo and Stefszky, Michael and Silberhorn, Christine}}, issn = {{2040-8978}}, journal = {{Journal of Optics}}, title = {{{General analytic theory of classical collinear three-wave mixing in a monolithic cavity}}}, doi = {{10.1088/2040-8986/ac0b90}}, year = {{2021}}, } @article{29524, author = {{De, Syamsundar and Gil López, Jano and Brecht, Benjamin and Silberhorn, Christine and Sánchez-Soto, Luis L. and Hradil, Zdeněk and Řeháček, Jaroslav}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, keywords = {{General Engineering}}, number = {{3}}, publisher = {{American Physical Society (APS)}}, title = {{{Effects of coherence on temporal resolution}}}, doi = {{10.1103/physrevresearch.3.033082}}, volume = {{3}}, year = {{2021}}, } @article{21020, author = {{Ansari, Vahid and Brecht, Benjamin and Gil-Lopez, Jano and Donohue, John M. and Řeháček, Jaroslav and Hradil, Zdeněk and Sánchez-Soto, Luis L. and Silberhorn, Christine}}, issn = {{2691-3399}}, journal = {{PRX Quantum}}, title = {{{Achieving the Ultimate Quantum Timing Resolution}}}, doi = {{10.1103/prxquantum.2.010301}}, volume = {{2}}, year = {{2021}}, } @article{22259, author = {{Roman-Rodriguez, V and Brecht, Benjamin and Srinivasan, K and Silberhorn, Christine and Treps, N and Diamanti, E and Parigi, V}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Continuous variable multimode quantum states via symmetric group velocity matching}}}, doi = {{10.1088/1367-2630/abef96}}, volume = {{23}}, year = {{2021}}, } @misc{38135, author = {{Padberg, Laura and Eigner, Christof and Santandrea, Matteo and Silberhorn, Christine}}, title = {{{Production of waveguides made of materials from the KTP family}}}, year = {{2021}}, } @inproceedings{40374, abstract = {{We present a frequency multimode integrated SU (1,1) interferometer with a polarization converter and strong signal-idler photon correlations. Phase sensitivity below the shot noise limit is demonstrated, various filtering and seeding strategies are discussed.}}, author = {{Ferreri, A. and Santandrea, Matteo and Stefszky, Michael and Luo, Kai Hong and Herrmann, Harald and Silberhorn, Christine and Sharapova, Polina}}, booktitle = {{Conference on Lasers and Electro-Optics}}, publisher = {{Optica Publishing Group}}, title = {{{Multimode integrated SU(1,1) interferometer}}}, doi = {{10.1364/cleo_qels.2021.ftu1n.6}}, year = {{2021}}, } @article{37936, author = {{Pelucchi, Emanuele and Fagas, Giorgos and Aharonovich, Igor and Englund, Dirk and Figueroa, Eden and Gong, Qihuang and Hannes, Hübel and Liu, Jin and Lu, Chao-Yang and Matsuda, Nobuyuki and Pan, Jian-Wei and Schreck, Florian and Sciarrino, Fabio and Silberhorn, Christine and Wang, Jianwei and Jöns, Klaus}}, issn = {{2522-5820}}, journal = {{Nature Reviews Physics}}, keywords = {{General Physics and Astronomy}}, number = {{3}}, pages = {{194--208}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{The potential and global outlook of integrated photonics for quantum technologies}}}, doi = {{10.1038/s42254-021-00398-z}}, volume = {{4}}, year = {{2021}}, } @article{22770, author = {{Gil López, Jano and Santandrea, Matteo and Roland, Ganaël and Brecht, Benjamin and Eigner, Christof and Ricken, Raimund and Quiring, Viktor and Silberhorn, Christine}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Improved non-linear devices for quantum applications}}}, doi = {{10.1088/1367-2630/ac09fd}}, year = {{2021}}, } @article{26410, author = {{Gil López, Jano and Teo, Yong Siah and De, Syamsundar and Brecht, Benjamin and Jeong, Hyunseok and Silberhorn, Christine and Sánchez-Soto, Luis L.}}, issn = {{2334-2536}}, journal = {{Optica}}, title = {{{Universal compressive tomography in the time-frequency domain}}}, doi = {{10.1364/optica.427645}}, year = {{2021}}, } @article{26889, author = {{Luo, Kai Hong and Santandrea, Matteo and Stefszky, Michael and Sperling, Jan and Massaro, Marcello and Ferreri, Alessandro and Sharapova, Polina and Herrmann, Harald and Silberhorn, Christine}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, title = {{{Quantum optical coherence: From linear to nonlinear interferometers}}}, doi = {{10.1103/physreva.104.043707}}, year = {{2021}}, } @article{26284, author = {{Bagrets, Dmitry and Kim, Kun Woo and Barkhofen, Sonja and De, Syamsundar and Sperling, Jan and Silberhorn, Christine and Altland, Alexander and Micklitz, Tobias}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, title = {{{Probing the topological Anderson transition with quantum walks}}}, doi = {{10.1103/physrevresearch.3.023183}}, year = {{2021}}, } @article{26287, author = {{Geraldi, Andrea and De, Syamsundar and Laneve, Alessandro and Barkhofen, Sonja and Sperling, Jan and Mataloni, Paolo and Silberhorn, Christine}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, title = {{{Transient subdiffusion via disordered quantum walks}}}, doi = {{10.1103/physrevresearch.3.023052}}, year = {{2021}}, } @article{21021, author = {{Tiedau, J. and Engelkemeier, M. and Brecht, Benjamin and Sperling, Jan and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Statistical Benchmarking of Scalable Photonic Quantum Systems}}}, doi = {{10.1103/physrevlett.126.023601}}, volume = {{126}}, year = {{2021}}, } @article{26286, author = {{Prasannan, Nidhin and De, Syamsundar and Barkhofen, Sonja and Brecht, Benjamin and Silberhorn, Christine and Sperling, Jan}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, title = {{{Experimental entanglement characterization of two-rebit states}}}, doi = {{10.1103/physreva.103.l040402}}, volume = {{103}}, year = {{2021}}, } @article{23826, abstract = {{Potassium titanyl phosphate (KTP) is a nonlinear optical material with applications in high-power frequency conversion or quasi-phase matching in submicron period domain grids. A prerequisite for these applications is a precise control and understanding of the poling mechanisms to enable the fabrication of high-grade domain grids. In contrast to the widely used material lithium niobate, the domain growth in KTP is less studied, because many standard methods, such as selective etching or polarization microscopy, provides less insight or are not applicable on non-polar surfaces, respectively. In this work, we present results of confocal Raman-spectroscopy of the ferroelectric domain structure in KTP. This analytical method allows for the visualization of domain grids of the non-polar KTP y-face and therefore more insight into the domain-growth and -structure in KTP, which can be used for improved domain fabrication.}}, author = {{Brockmeier, Julian and Mackwitz, Peter Walter Martin and Rüsing, Michael and Eigner, Christof and Padberg, Laura and Santandrea, Matteo and Silberhorn, Christine and Zrenner, Artur and Berth, Gerhard}}, issn = {{2073-4352}}, journal = {{Crystals}}, title = {{{Non-Invasive Visualization of Ferroelectric Domain Structures on the Non-Polar y-Surface of KTiOPO4 via Raman Imaging}}}, doi = {{10.3390/cryst11091086}}, year = {{2021}}, } @article{26223, author = {{Santandrea, Matteo and Stefszky, Michael and Roeland, Ganaël and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, title = {{{Interferometric method for determining the losses of spatially multi-mode nonlinear waveguides based on second harmonic generation}}}, doi = {{10.1364/oe.380788}}, year = {{2020}}, } @article{22771, author = {{Stefszky, Michael and Santandrea, Matteo and vom Bruch, Felix and Krapick, S. and Eigner, Christof and Ricken, R. and Quiring, V. and Herrmann, Harald and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, title = {{{Waveguide resonator with an integrated phase modulator for second harmonic generation}}}, doi = {{10.1364/oe.412824}}, year = {{2020}}, } @article{37933, abstract = {{We present a time-over-threshold readout technique to count the number of activated pixels from an array of superconducting nanowire single photon detectors (SNSPDs). This technique places no additional heatload on the cryostat, and retains the intrinsic count rate of the time-tagger. We demonstrate proof-of-principle operation with respect to a four-pixel device. Furthermore, we show that, given some permissible error threshold, the number of pixels that can be reliably read out scales linearly with the intrinsic signal-to-noise ratio of the individual pixel response.}}, author = {{Tiedau, Johannes and Schapeler, Timon and Anant, Vikas and Fedder, Helmut and Silberhorn, Christine and Bartley, Tim}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{4}}, publisher = {{Optica Publishing Group}}, title = {{{Single-channel electronic readout of a multipixel superconducting nanowire single photon detector}}}, doi = {{10.1364/oe.383111}}, volume = {{28}}, year = {{2020}}, } @article{38051, abstract = {{The characterisation of loss in optical waveguides is essential in understanding the performance of these devices and their limitations. Whilst interferometric-based methods generally provide the best results for low-loss waveguides, they are almost exclusively used to provide characterization in cases where the waveguide is spatially single-mode. Here, we introduce a Fabry-Pérot-based scheme to estimate the losses of a nonlinear (birefringent or quasi-phase matched) waveguide at a wavelength where it is multi-mode. The method involves measuring the generated second harmonic power as the pump wavelength is scanned over the phase matching region. Furthermore, it is shown that this method allows one to infer the losses of different second harmonic spatial modes by scanning the pump field over the separated phase matching spectra. By fitting the measured phase matching spectra from different titanium indiffused lithium niobate waveguides to the model presented in this paper, it is shown that one can estimate the second harmonic losses of a single spatial-mode, at wavelengths where the waveguides are spatially multi-mode.}}, author = {{Santandrea, Matteo and Stefszky, Michael and Roeland, Ganaël and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{4}}, publisher = {{Optica Publishing Group}}, title = {{{Interferometric method for determining the losses of spatially multi-mode nonlinear waveguides based on second harmonic generation.}}}, doi = {{10.1364/oe.380788}}, volume = {{28}}, year = {{2020}}, } @article{37934, author = {{Mukamel, Shaul and Freyberger, Matthias and Schleich, Wolfgang and Bellini, Marco and Zavatta, Alessandro and Leuchs, Gerd and Silberhorn, Christine and Boyd, Robert W and Sánchez-Soto, Luis Lorenzo and Stefanov, André and Barbieri, Marco and Paterova, Anna and Krivitsky, Leonid and Shwartz, Sharon and Tamasaku, Kenji and Dorfman, Konstantin and Schlawin, Frank and Sandoghdar, Vahid and Raymer, Michael and Marcus, Andrew and Varnavski, Oleg and Goodson, Theodore and Zhou, Zhi-Yuan and Shi, Bao-Sen and Asban, Shahaf and Scully, Marlan and Agarwal, Girish and Peng, Tao and Sokolov, Alexei V and Zhang, Zhe-Dong and Zubairy, M Suhail and Vartanyants, Ivan A and del Valle, Elena and Laussy, Fabrice}}, issn = {{0953-4075}}, journal = {{Journal of Physics B: Atomic, Molecular and Optical Physics}}, keywords = {{Condensed Matter Physics, Atomic and Molecular Physics, and Optics}}, number = {{7}}, publisher = {{IOP Publishing}}, title = {{{Roadmap on quantum light spectroscopy}}}, doi = {{10.1088/1361-6455/ab69a8}}, volume = {{53}}, year = {{2020}}, } @article{37935, author = {{Meyer-Scott, Evan and Silberhorn, Christine and Migdall, Alan}}, issn = {{0034-6748}}, journal = {{Review of Scientific Instruments}}, keywords = {{Instrumentation}}, number = {{4}}, publisher = {{AIP Publishing}}, title = {{{Single-photon sources: Approaching the ideal through multiplexing}}}, doi = {{10.1063/5.0003320}}, volume = {{91}}, year = {{2020}}, } @article{37932, abstract = {{Hybrid quantum information processing combines the advantages of discrete and continues variable protocols by realizing protocols consisting of photon counting and homodyne measurements. However, the mode structure of pulsed sources and the properties of the detection schemes often require the use of optical filters in order to combine both detection methods in a common experiment. This limits the efficiency and the overall achievable squeezing of the experiment. In our work, we use photon subtraction to implement the distillation of pulsed squeezed states originating from a genuinely spatially and temporally single-mode parametric down-conversion source in non-linear waveguides. Due to the distillation, we witness an improvement of 0.17 dB from an initial squeezing value of −1.648 ± 0.002 dB, while achieving a purity of 0.58, and confirm the non-Gaussianity of the distilled state via the higher-order cumulants. With this, we demonstrate the source’s suitability for scalable hybrid quantum network applications with pulsed quantum light.}}, author = {{Dirmeier, Thomas and Tiedau, Johannes and Khan, Imran and Ansari, Vahid and Müller, Christian R. and Silberhorn, Christine and Marquardt, Christoph and Leuchs, Gerd}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{21}}, publisher = {{Optica Publishing Group}}, title = {{{Distillation of squeezing using an engineered pulsed parametric down-conversion source}}}, doi = {{10.1364/oe.402178}}, volume = {{28}}, year = {{2020}}, } @article{21025, author = {{Eigner, Christof and Padberg, Laura and Santandrea, Matteo and Herrmann, Harald and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, number = {{22}}, title = {{{Spatially single mode photon pair source at 800 nm in periodically poled Rubidium exchanged KTP waveguides}}}, doi = {{10.1364/oe.399483}}, volume = {{28}}, year = {{2020}}, } @article{40381, abstract = {{Abstract The phenomenon of entanglement is the basis of quantum information and quantum communication processes. Entangled systems with a large number of photons are of great interest at present because they provide a platform for streaming technologies based on photonics. In this paper we present a device which operates with four-photons and based on the Hong–Ou–Mandel interference. The presented device allows to maximize the degree of spatial entanglement and generate the highly entangled four-dimensional Bell states. Furthermore, the use of the interferometer in different regimes leads to fast interference fringes in the coincidence probability with period of oscillations twice smaller than the pump wavelength. We have a good agreement between theoretical simulations and experimental results.}}, author = {{Ferreri, A and Ansari, V and Brecht, Benjamin and Silberhorn, Christine and Sharapova, Polina R.}}, issn = {{2058-9565}}, journal = {{Quantum Science and Technology}}, keywords = {{Electrical and Electronic Engineering, Physics and Astronomy (miscellaneous), Materials Science (miscellaneous), Atomic and Molecular Physics, and Optics}}, number = {{4}}, publisher = {{IOP Publishing}}, title = {{{Spatial entanglement and state engineering via four-photon Hong–Ou–Mandel interference}}}, doi = {{10.1088/2058-9565/abb411}}, volume = {{5}}, year = {{2020}}, } @article{26294, author = {{Sperling, Jan and Phillips, D. S. and Bulmer, J. F. F and Thekkadath, G. S. and Eckstein, A. and Wolterink, T. A. W. and Lugani, J. and Nam, S. W. and Lita, A. and Gerrits, T. and Vogel, W. and Agarwal, G. S. and Silberhorn, Christine and Walmsley, I. A.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Detector-Agnostic Phase-Space Distributions}}}, doi = {{10.1103/physrevlett.124.013605}}, year = {{2020}}, } @article{21023, author = {{Engelkemeier, M. and Lorz, L. and De, Syamsundar and Brecht, Benjamin and Dhand, I. and Plenio, M. B. and Silberhorn, Christine and Sperling, Jan}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, title = {{{Quantum photonics with active feedback loops}}}, doi = {{10.1103/physreva.102.023712}}, volume = {{102}}, year = {{2020}}, } @article{26289, author = {{Nitsche, Thomas and De, Syamsundar and Barkhofen, Sonja and Meyer-Scott, Evan and Tiedau, Johannes and Sperling, Jan and Gábris, Aurél and Jex, Igor and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Local Versus Global Two-Photon Interference in Quantum Networks}}}, doi = {{10.1103/physrevlett.125.213604}}, year = {{2020}}, } @article{19190, abstract = {{Polarons in dielectric crystals play a crucial role for applications in integrated electronics and optoelectronics. In this work, we use density-functional theory and Green's function methods to explore the microscopic structure and spectroscopic signatures of electron polarons in lithium niobate (LiNbO3). Total-energy calculations and the comparison of calculated electron paramagnetic resonance data with available measurements reveal the formation of bound polarons at Nb_Li antisite defects with a quasi-Jahn-Teller distorted, tilted configuration. The defect-formation energies further indicate that (bi)polarons may form not only at Nb_Li antisites but also at structures where the antisite Nb atom moves into a neighboring empty oxygen octahedron. Based on these structure models, and on the calculated charge-transition levels and potential-energy barriers, we propose two mechanisms for the optical and thermal splitting of bipolarons, which provide a natural explanation for the reported two-path recombination of bipolarons. Optical-response calculations based on the Bethe-Salpeter equation, in combination with available experimental data and new measurements of the optical absorption spectrum, further corroborate the geometries proposed here for free and defect-bound (bi)polarons.}}, author = {{Schmidt, Falko and Kozub, Agnieszka L. and Biktagirov, Timur and Eigner, Christof and Silberhorn, Christine and Schindlmayr, Arno and Schmidt, Wolf Gero and Gerstmann, Uwe}}, issn = {{2643-1564}}, journal = {{Physical Review Research}}, number = {{4}}, publisher = {{American Physical Society}}, title = {{{Free and defect-bound (bi)polarons in LiNbO3: Atomic structure and spectroscopic signatures from ab initio calculations}}}, doi = {{10.1103/PhysRevResearch.2.043002}}, volume = {{2}}, year = {{2020}}, } @article{20682, author = {{Bocchini, Adriana and Eigner, Christof and Silberhorn, Christine and Schmidt, Wolf Gero and Gerstmann, Uwe}}, journal = {{Phys. Rev. Materials}}, pages = {{124402}}, publisher = {{American Physical Society}}, title = {{{Understanding gray track formation in KTP: Ti^3+ centers studied from first principles}}}, doi = {{10.1103/PhysRevMaterials.4.124402}}, volume = {{4}}, year = {{2020}}, } @article{25920, author = {{Padberg, Laura and Santandrea, Matteo and Rüsing, Michael and Brockmeier, Julian and Mackwitz, Peter and Berth, Gerhard and Zrenner, Artur and Eigner, Christof and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, title = {{{Characterisation of width-dependent diffusion dynamics in rubidium-exchanged KTP waveguides}}}, doi = {{10.1364/oe.397074}}, year = {{2020}}, } @article{25038, author = {{Massaro, Marcello and Meyer-Scott, Evan and Montaut, Nicola and Herrmann, Harald and Silberhorn, Christine}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Improving SPDC single-photon sources via extended heralding and feed-forward control}}}, doi = {{10.1088/1367-2630/ab1ec3}}, year = {{2019}}, } @article{26224, author = {{Santandrea, Matteo and Stefszky, Michael and Roeland, Ganaël and Silberhorn, Christine}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Characterisation of fabrication inhomogeneities in Ti:LiNbO3 waveguides}}}, doi = {{10.1088/1367-2630/ab5cb5}}, year = {{2019}}, } @article{26226, author = {{Santandrea, Matteo and Stefszky, Michael and Ansari, Vahid and Silberhorn, Christine}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Fabrication limits of waveguides in nonlinear crystals and their impact on quantum optics applications}}}, doi = {{10.1088/1367-2630/aaff13}}, year = {{2019}}, } @article{26237, author = {{Luo, Kai-Hong and Ansari, Vahid and Massaro, Marcello and Santandrea, Matteo and Eigner, Christof and Ricken, Raimund and Herrmann, Harald and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, title = {{{Counter-propagating photon pair generation in a nonlinear waveguide}}}, doi = {{10.1364/oe.378789}}, year = {{2019}}, } @inproceedings{9635, author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Montaut, Nicola and Tiedau, Johannes and Eigner, Christof and Harder, Georg and Sansoni, Linda and Nitsche, Thomas and Herrmann, Harald and Ricken, Raimund and Quiring, Viktor and Bartley, Tim and Barkhofen, Sonja and Silberhorn, Christine}}, booktitle = {{Advances in Photonics of Quantum Computing, Memory, and Communication XII}}, editor = {{Hasan, Zameer U. and Hemmer, Philip R. and Migdall, Alan L.}}, isbn = {{9781510625082}}, title = {{{Engineering integrated photon pair sources and multiplexed detectors (Conference Presentation)}}}, doi = {{10.1117/12.2513753}}, year = {{2019}}, } @misc{38138, author = {{Padberg, Laura and Eigner, Christof and Santandrea, Matteo and Silberhorn, Christine}}, title = {{{Herstellung von Wellenleitern aus Materialien der KTP-Familie}}}, year = {{2019}}, } @article{38047, author = {{Xie, Zhenda and Luo, Kai Hong and Chang, Kai Chi and Panoiu, Nicolae C. and Herrmann, Harald and Silberhorn, Christine and Wong, Chee Wei}}, issn = {{1559-128X}}, journal = {{Applied Optics}}, keywords = {{Atomic and Molecular Physics, and Optics, Engineering (miscellaneous), Electrical and Electronic Engineering}}, number = {{22}}, publisher = {{The Optical Society}}, title = {{{Efficient C-band single-photon upconversion with chip-scale Ti-indiffused pp-LiNbO3 waveguides}}}, doi = {{10.1364/ao.58.005910}}, volume = {{58}}, year = {{2019}}, } @article{38046, author = {{Faruque, Imad I. and Sinclair, Gary F. and Bonneau, Damien and Ono, Takafumi and Silberhorn, Christine and Thompson, Mark G. and Rarity, John G.}}, issn = {{2331-7019}}, journal = {{Physical Review Applied}}, keywords = {{General Physics and Astronomy}}, number = {{5}}, publisher = {{American Physical Society (APS)}}, title = {{{Estimating the Indistinguishability of Heralded Single Photons Using Second-Order Correlation}}}, doi = {{10.1103/physrevapplied.12.054029}}, volume = {{12}}, year = {{2019}}, } @article{40384, author = {{Ferreri, Alessandro and Ansari, V. and Silberhorn, Christine and Sharapova, Polina R.}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{5}}, publisher = {{American Physical Society (APS)}}, title = {{{Temporally multimode four-photon Hong-Ou-Mandel interference}}}, doi = {{10.1103/physreva.100.053829}}, volume = {{100}}, year = {{2019}}, } @article{26296, author = {{Sperling, Jan and Perez-Leija, Armando and Busch, Kurt and Silberhorn, Christine}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, title = {{{Mode-independent quantum entanglement for light}}}, doi = {{10.1103/physreva.100.062129}}, year = {{2019}}, } @article{26300, author = {{Sperling, Jan and Meyer-Scott, E. and Barkhofen, Sonja and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Experimental Reconstruction of Entanglement Quasiprobabilities}}}, doi = {{10.1103/physrevlett.122.053602}}, year = {{2019}}, } @inproceedings{9677, author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Montaut, Nicola and Tiedau, Johannes and Harder, Georg and Sansoni, Linda and Herrmann, Harald and Eigner, Christof and Ricken, Raimund and Quiring, Viktor and Bartley, Tim and Barkhofen, Sonja and Silberhorn, Christine}}, booktitle = {{Frontiers in Optics / Laser Science}}, isbn = {{9781943580460}}, title = {{{Engineering integrated sources of entangled photon pairs}}}, doi = {{10.1364/ls.2018.lm3b.1}}, year = {{2018}}, } @inproceedings{9678, author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Montaut, Nicola and Tiedau, Johannes and Harder, Georg and Sansoni, Linda and Herrmann, Harald and Eigner, Christof and Ricken, Raimund and Quiring, Viktor and Bartley, Tim J. and Barkhofen, Sonja and Silberhorn, Christine}}, booktitle = {{Frontiers in Optics / Laser Science}}, isbn = {{9781943580460}}, title = {{{Engineering integrated sources of entangled photon pairs}}}, doi = {{10.1364/ls.2018.lm3b.1}}, year = {{2018}}, } @article{9638, author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Eigner, Christof and Quiring, Viktor and Donohue, John M. and Barkhofen, Sonja and Silberhorn, Christine}}, issn = {{1094-4087}}, journal = {{Optics Express}}, title = {{{High-performance source of spectrally pure, polarization entangled photon pairs based on hybrid integrated-bulk optics}}}, doi = {{10.1364/oe.26.032475}}, year = {{2018}}, } @article{9679, author = {{Stefszky, Michael and Ricken, R and Eigner, Christof and Quiring, V and Herrmann, Harald and Silberhorn, Christine}}, issn = {{2040-8978}}, journal = {{Journal of Optics}}, title = {{{High-power waveguide resonator second harmonic device with external conversion efficiency up to 75%}}}, doi = {{10.1088/2040-8986/aac1d5}}, year = {{2018}}, } @article{38052, author = {{Montaut, Nicola and Magaña-Loaiza, Omar S. and Bartley, Tim and Verma, Varun B. and Nam, Sae Woo and Mirin, Richard P. and Silberhorn, Christine and Gerrits, Thomas}}, issn = {{2334-2536}}, journal = {{Optica}}, keywords = {{Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}}, number = {{11}}, publisher = {{The Optical Society}}, title = {{{Compressive characterization of telecom photon pairs in the spatial and spectral degrees of freedom}}}, doi = {{10.1364/optica.5.001418}}, volume = {{5}}, year = {{2018}}, } @article{21029, author = {{Allgaier, Markus and Ansari, Vahid and Eigner, Christof and Quiring, Viktor and Ricken, Raimund and Donohue, John Matthew and Czerniuk, Thomas and Aßmann, Marc and Bayer, Manfred and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, title = {{{Streak camera imaging of single photons at telecom wavelength}}}, doi = {{10.1063/1.5004110}}, volume = {{112}}, year = {{2018}}, } @article{38054, author = {{Donohue, J. M. and Ansari, V. and Řeháček, J. and Hradil, Z. and Stoklasa, B. and Paúr, M. and Sánchez-Soto, L. L. and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{9}}, publisher = {{American Physical Society (APS)}}, title = {{{Quantum-Limited Time-Frequency Estimation through Mode-Selective Photon Measurement}}}, doi = {{10.1103/physrevlett.121.090501}}, volume = {{121}}, year = {{2018}}, } @inproceedings{40386, author = {{Sharapova, Polina and Luo, Kai Hong and Herrmann, Harald and Reichelt, Matthias and Silberhorn, Christine and Meier, Torsten}}, booktitle = {{Conference on Lasers and Electro-Optics}}, isbn = {{978-1-943580-42-2}}, location = {{San Jose, California United States}}, publisher = {{OSA}}, title = {{{Manipulation of Two-Photon Interference by Entanglement}}}, doi = {{10.1364/cleo_qels.2018.ff1b.8}}, year = {{2018}}, } @article{26305, author = {{Bohmann, M. and Tiedau, J. and Bartley, Tim and Sperling, Jan and Silberhorn, Christine and Vogel, W.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Incomplete Detection of Nonclassical Phase-Space Distributions}}}, doi = {{10.1103/physrevlett.120.063607}}, year = {{2018}}, } @inproceedings{40388, author = {{Luo, Kai Hong and Brauner, Sebastian and Eigner, Christof and Sharapova, Polina and Ricken, Raimund and Meier, Torsten and Herrmann, Harald and Silberhorn, Christine}}, booktitle = {{Conference on Lasers and Electro-Optics}}, isbn = {{978-1-943580-42-2}}, location = {{San Jose, California United States}}, publisher = {{OSA}}, title = {{{Monolithically Integrated Hong-Ou-Mandel Experiment in LiNbO3}}}, doi = {{10.1364/cleo_qels.2018.fm1g.3}}, year = {{2018}}, } @article{4769, abstract = {{In recent years, Raman spectroscopy has been used to visualize and analyze ferroelectric domain structures. The technique makes use of the fact that the intensity or frequency of certain phonons is strongly influenced by the presence of domain walls. Although the method is used frequently, the underlying mechanism responsible for the changes in the spectra is not fully understood. This inhibits deeper analysis of domain structures based on this method. Two different models have been proposed. However, neither model completely explains all observations. In this work, we have systematically investigated domain walls in different scattering geometries with Raman spectroscopy in the common ferroelectric materials used in integrated optics, i.e., KTiOPO4, LiNbO3, and LiTaO3. Based on the two models, we can demonstrate that the observed contrast for domain walls is in fact based on two different effects. We can identify on the one hand microscopic changes at the domain wall, e.g., strain and electric fields, and on the other hand a macroscopic change of selection rules at the domain wall. While the macroscopic relaxation of selection rules can be explained by the directional dispersion of the phonons in agreement with previous propositions, the microscopic changes can be explained qualitatively in terms of a simplified atomistic model.}}, author = {{Rüsing, Michael and Neufeld, Sergej and Brockmeier, Julian and Eigner, Christof and Mackwitz, P. and Spychala, K. and Silberhorn, Christine and Schmidt, Wolf Gero and Berth, Gerhard and Zrenner, Artur and Sanna, S.}}, issn = {{2475-9953}}, journal = {{Physical Review Materials}}, number = {{10}}, publisher = {{American Physical Society (APS)}}, title = {{{Imaging of 180∘ ferroelectric domain walls in uniaxial ferroelectrics by confocal Raman spectroscopy: Unraveling the contrast mechanism}}}, doi = {{10.1103/physrevmaterials.2.103801}}, volume = {{2}}, year = {{2018}}, } @article{9681, author = {{Volk, Martin F. and Rüter, Christian E. and Santandrea, Matteo and Eigner, Christof and Padberg, Laura and Herrmann, Harald and Silberhorn, Christine and Kip, Detlef}}, issn = {{2159-3930}}, journal = {{Optical Materials Express}}, title = {{{Fabrication of low-loss Rb-exchanged ridge waveguides in z-cut KTiOPO_4}}}, doi = {{10.1364/ome.8.000082}}, year = {{2017}}, } @inproceedings{9682, author = {{Brecht, Benjamin and Lazo-Arjona, O. and Kaczmarek, K. T. and Parker, T. and Ricken, R. and Quiring, V. and Eigner, Christof and Luo, K. H. and Herrmann, Harald and Silberhorn, Christine and Walmsley, I. A.}}, booktitle = {{Frontiers in Optics 2017}}, isbn = {{9781943580330}}, title = {{{A monolithic, doubly-resonant parametric down-conversion source for Caesium Raman memories}}}, doi = {{10.1364/fio.2017.jw4a.3}}, year = {{2017}}, } @article{9684, author = {{Stefszky, M. and Ricken, R. and Eigner, Christof and Quiring, V. and Herrmann, Harald and Silberhorn, Christine}}, issn = {{2331-7019}}, journal = {{Physical Review Applied}}, title = {{{Waveguide Cavity Resonator as a Source of Optical Squeezing}}}, doi = {{10.1103/physrevapplied.7.044026}}, year = {{2017}}, } @article{9685, author = {{Sansoni, Linda and Luo, Kai Hong and Eigner, Christof and Ricken, Raimund and Quiring, Viktor and Herrmann, Harald and Silberhorn, Christine}}, issn = {{2056-6387}}, journal = {{npj Quantum Information}}, title = {{{A two-channel, spectrally degenerate polarization entangled source on chip}}}, doi = {{10.1038/s41534-016-0005-z}}, year = {{2017}}, } @misc{31301, author = {{Schütte, Philipp}}, title = {{{Identifying and Realizing Symmetries in Quantum Walks - Symmetry Classes and Quantum Walks}}}, year = {{2017}}, } @article{9832, author = {{Kruse, Regina and Tiedau, Johannes and Bartley, Tim and Barkhofen, Sonja and Silberhorn, Christine}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, title = {{{Limits of the time-multiplexed photon-counting method}}}, doi = {{10.1103/physreva.95.023815}}, year = {{2017}}, } @article{9833, author = {{Barkhofen, Sonja and Bartley, Tim and Sansoni, Linda and Kruse, Regina and Hamilton, Craig S. and Jex, Igor and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Driven Boson Sampling}}}, doi = {{10.1103/physrevlett.118.020502}}, year = {{2017}}, } @article{38058, author = {{Montaut, Nicola and Sansoni, Linda and Meyer-Scott, Evan and Ricken, Raimund and Quiring, Viktor and Herrmann, Harald and Silberhorn, Christine}}, issn = {{2331-7019}}, journal = {{Physical Review Applied}}, keywords = {{General Physics and Astronomy}}, number = {{2}}, publisher = {{American Physical Society (APS)}}, title = {{{High-Efficiency Plug-and-Play Source of Heralded Single Photons}}}, doi = {{10.1103/physrevapplied.8.024021}}, volume = {{8}}, year = {{2017}}, } @article{38056, author = {{Mogilevtsev, D and Teo, Y S and Řeháček, J and Hradil, Z and Tiedau, J and Kruse, R and Harder, G and Silberhorn, Christine and Sanchez-Soto, L L}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, keywords = {{General Physics and Astronomy}}, number = {{9}}, publisher = {{IOP Publishing}}, title = {{{Extracting the physical sector of quantum states}}}, doi = {{10.1088/1367-2630/aa81b3}}, volume = {{19}}, year = {{2017}}, } @article{21032, abstract = {{In the last few decades, there has been much progress on low loss waveguides, very efficient photon-number detectors and nonlinear processes. Engineered sum-frequency conversion is now at a stage where it allows operation on arbitrary temporal broadband modes, thus making the spectral degree of freedom accessible for information coding. Hereby the information is often encoded into the temporal modes of a single photon. Here, we analyse the prospect of using multi-photon states or squeezed states in different temporal modes based on integrated optics devices. We describe an analogy between mode-selective sum-frequency conversion and a network of spatial beam splitters. Furthermore, we analyse the limits on the achievable squeezing in waveguides with current technology and the loss limits in the conversion process. This article is part of the themed issue ‘Quantum technology for the 21st century’.}}, author = {{Harder, G. and Ansari, V. and Bartley, Tim and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{1364-503X}}, journal = {{Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences}}, number = {{2099}}, title = {{{Harnessing temporal modes for multi-photon quantum information processing based on integrated optics}}}, doi = {{10.1098/rsta.2016.0244}}, volume = {{375}}, year = {{2017}}, } @article{21031, author = {{Allgaier, Markus and Vigh, Gesche and Ansari, Vahid and Eigner, Christof and Quiring, Viktor and Ricken, Raimund and Brecht, Benjamin and Silberhorn, Christine}}, issn = {{2058-9565}}, journal = {{Quantum Science and Technology}}, title = {{{Fast time-domain measurements on telecom single photons}}}, doi = {{10.1088/2058-9565/aa7abb}}, volume = {{2}}, year = {{2017}}, } @article{13906, author = {{Sharapova, Polina and Luo, Kai Hong and Herrmann, Harald and Reichelt, Matthias and Meier, Torsten and Silberhorn, Christine}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, number = {{12}}, publisher = {{IOP Publishing}}, title = {{{Toolbox for the design of LiNbO3-based passive and active integrated quantum circuits}}}, doi = {{10.1088/1367-2630/aa9033}}, volume = {{19}}, year = {{2017}}, } @article{13905, author = {{Sharapova, Polina and Luo, Kai Hong and Herrmann, Harald and Reichelt, Matthias and Silberhorn, Christine and Meier, Torsten}}, issn = {{2469-9926}}, journal = {{Physical Review A}}, number = {{4}}, pages = {{043857}}, publisher = {{American Physical Society}}, title = {{{Modified two-photon interference achieved by the manipulation of entanglement}}}, doi = {{10.1103/physreva.96.043857}}, volume = {{96}}, year = {{2017}}, } @article{26061, author = {{Sharapova, Polina and Luo, Kai Hong and Herrmann, Harald and Reichelt, Matthias and Meier, Torsten and Silberhorn, Christine}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, number = {{12}}, publisher = {{IOP Publishing}}, title = {{{Toolbox for the design of LiNbO3-based passive and active integrated quantum circuits}}}, doi = {{10.1088/1367-2630/aa9033}}, volume = {{19}}, year = {{2017}}, } @inproceedings{13903, author = {{Höpker, Jan Philipp and Bartnick, Moritz and Meyer-Scott, Evan and Thiele, Frederik and Meier, Torsten and Bartley, Tim and Krapick, Stephan and Montaut, Nicola M. and Santandrea, Matteo and Herrmann, Harald and Lengeling, Sebastian and Ricken, Raimund and Quiring, Viktor and Lita, Adriana E. and Verma, Varun B. and Gerrits, Thomas and Nam, Sae Woo and Silberhorn, Christine}}, booktitle = {{Quantum Photonic Devices}}, editor = {{Agio, Mario and Srinivasan, Kartik and Soci, Cesare}}, isbn = {{9781510611733}}, pages = {{1035809}}, publisher = {{SPIE}}, title = {{{Towards integrated superconducting detectors on lithium niobate waveguides}}}, doi = {{10.1117/12.2273388}}, volume = {{10358}}, year = {{2017}}, } @article{38061, author = {{Schleich, Wolfgang P. and Ranade, Kedar S. and Anton, Christian and Arndt, Markus and Aspelmeyer, Markus and Bayer, Manfred and Berg, Gunnar and Calarco, Tommaso and Fuchs, Harald and Giacobino, Elisabeth and Grassl, Markus and Hänggi, Peter and Heckl, Wolfgang M. and Hertel, Ingolf-Volker and Huelga, Susana and Jelezko, Fedor and Keimer, Bernhard and Kotthaus, Jörg P. and Leuchs, Gerd and Lütkenhaus, Norbert and Maurer, Ueli and Pfau, Tilman and Plenio, Martin B. and Rasel, Ernst Maria and Renn, Ortwin and Silberhorn, Christine and Schiedmayer, Jörg and Schmitt-Landsiedel, Doris and Schönhammer, Kurt and Ustinov, Alexey and Walther, Philip and Weinfurter, Harald and Welzl, Emo and Wiesendanger, Roland and Wolf, Stefan and Zeilinger, Anton and Zoller, Peter}}, issn = {{0946-2171}}, journal = {{Applied Physics B}}, keywords = {{General Physics and Astronomy, Physics and Astronomy (miscellaneous), General Engineering}}, number = {{5}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Quantum technology: from research to application}}}, doi = {{10.1007/s00340-016-6353-8}}, volume = {{122}}, year = {{2016}}, } @article{38068, author = {{Szemendera, L. and Darré, P. and Baudoin, R. and Grossard, L. and Delage, L. and Herrmann, Harald and Silberhorn, Christine and Reynaud, F.}}, issn = {{0035-8711}}, journal = {{Monthly Notices of the Royal Astronomical Society}}, keywords = {{Space and Planetary Science, Astronomy and Astrophysics}}, number = {{3}}, pages = {{3115--3118}}, publisher = {{Oxford University Press (OUP)}}, title = {{{In-lab ALOHA mid-infrared up-conversion interferometer with high fringe contrast @λ = 3.39 μm}}}, doi = {{10.1093/mnras/stw196}}, volume = {{457}}, year = {{2016}}, } @article{38071, author = {{Harder, G. and Silberhorn, Christine and Rehacek, J. and Hradil, Z. and Motka, L. and Stoklasa, B. and Sánchez-Soto, L. L.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{13}}, publisher = {{American Physical Society (APS)}}, title = {{{Local Sampling of the Wigner Function at Telecom Wavelength with Loss-Tolerant Detection of Photon Statistics}}}, doi = {{10.1103/physrevlett.116.133601}}, volume = {{116}}, year = {{2016}}, } @article{4239, abstract = {{Confocal Raman spectroscopy is applied to identify ferroelectric domain structure sensitive phonon modes in potassium titanyl phosphate. Therefore, polarization-dependent measurements in various scattering configurations have been performed to characterize the fundamental Raman spectra of the material. The obtained spectra are discussed qualitatively based on an internal mode assignment. In the main part of this work, we have characterized z-cut periodically poled potassium titanyl phosphate in terms of polarity- and structure-sensitive phonon modes. Here, we find vibrations whose intensities are linked to the ferroelectric domain walls. We interpret this in terms of changes in the polarizability originating from strain induced by domain boundaries and the inner field distribution. Hence, a direct and 3D visualization of ferroelectric domain structures becomes possible in potassium titanyl phosphate.}}, author = {{Rüsing, Michael and Eigner, Christof and Mackwitz, P. and Berth, Gerhard and Silberhorn, Christine and Zrenner, Artur}}, issn = {{0021-8979}}, journal = {{Journal of Applied Physics}}, number = {{4}}, publisher = {{AIP Publishing}}, title = {{{Identification of ferroelectric domain structure sensitive phonon modes in potassium titanyl phosphate: A fundamental study}}}, doi = {{10.1063/1.4940964}}, volume = {{119}}, year = {{2016}}, } @article{38086, author = {{Tiranov, Alexey and Lavoie, Jonathan and Ferrier, Alban and Goldner, Philippe and Verma, Varun B. and Nam, Sae Woo and Mirin, Richard P. and Lita, Adriana E. and Marsili, Francesco and Herrmann, Harald and Silberhorn, Christine and Gisin, Nicolas and Afzelius, Mikael and Bussières, Félix}}, issn = {{2334-2536}}, journal = {{Optica}}, keywords = {{Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}}, number = {{4}}, publisher = {{The Optical Society}}, title = {{{Storage of hyperentanglement in a solid-state quantum memory}}}, doi = {{10.1364/optica.2.000279}}, volume = {{2}}, year = {{2015}}, } @article{38087, author = {{Covi, M. and Pressl, B. and Günthner, T. and Laiho, K. and Krapick, Stefan and Silberhorn, Christine and Weihs, G.}}, issn = {{0946-2171}}, journal = {{Applied Physics B}}, keywords = {{General Physics and Astronomy, Physics and Astronomy (miscellaneous), General Engineering}}, number = {{3}}, pages = {{489--495}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Liquid-nitrogen cooled, free-running single-photon sensitive detector at telecommunication wavelengths}}}, doi = {{10.1007/s00340-015-6019-y}}, volume = {{118}}, year = {{2015}}, } @article{26333, author = {{Sperling, Jan and Bohmann, M. and Vogel, W. and Harder, G. and Brecht, Benjamin and Ansari, V. and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, title = {{{Uncovering Quantum Correlations with Time-Multiplexed Click Detection}}}, doi = {{10.1103/physrevlett.115.023601}}, year = {{2015}}, } @article{31296, author = {{Barkhofen, Sonja and Faure, F and Weich, Tobias}}, issn = {{0951-7715}}, journal = {{Nonlinearity}}, keywords = {{Applied Mathematics, General Physics and Astronomy, Mathematical Physics, Statistical and Nonlinear Physics}}, number = {{8}}, pages = {{1829--1858}}, publisher = {{IOP Publishing}}, title = {{{Resonance chains in open systems, generalized zeta functions and clustering of the length spectrum}}}, doi = {{10.1088/0951-7715/27/8/1829}}, volume = {{27}}, year = {{2014}}, } @article{38088, author = {{Shayovitz, Dror and Herrmann, Harald and Sohler, Wolfgang and Ricken, Raimund and Silberhorn, Christine and Marom, Dan M.}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{25}}, publisher = {{The Optical Society}}, title = {{{Real-time coherent detection of phase modulated ultrashort pulses after time-to-space conversion and spatial demultiplexing}}}, doi = {{10.1364/oe.22.031138}}, volume = {{22}}, year = {{2014}}, } @article{38089, author = {{Harder, G. and Silberhorn, Christine and Rehacek, J. and Hradil, Z. and Motka, L. and Stoklasa, B. and Sánchez-Soto, L. L.}}, issn = {{1050-2947}}, journal = {{Physical Review A}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{4}}, publisher = {{American Physical Society (APS)}}, title = {{{Time-multiplexed measurements of nonclassical light at telecom wavelengths}}}, doi = {{10.1103/physreva.90.042105}}, volume = {{90}}, year = {{2014}}, } @article{38090, author = {{Bussières, Félix and Clausen, Christoph and Tiranov, Alexey and Korzh, Boris and Verma, Varun B. and Nam, Sae Woo and Marsili, Francesco and Ferrier, Alban and Goldner, Philippe and Herrmann, Harald and Silberhorn, Christine and Sohler, Wolfgang and Afzelius, Mikael and Gisin, Nicolas}}, issn = {{1749-4885}}, journal = {{Nature Photonics}}, keywords = {{Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials}}, number = {{10}}, pages = {{775--778}}, publisher = {{Springer Science and Business Media LLC}}, title = {{{Quantum teleportation from a telecom-wavelength photon to a solid-state quantum memory}}}, doi = {{10.1038/nphoton.2014.215}}, volume = {{8}}, year = {{2014}}, } @article{38091, author = {{Clausen, C and Bussières, F and Tiranov, A and Herrmann, Harald and Silberhorn, Christine and Sohler, W and Afzelius, M and Gisin, N}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, keywords = {{General Physics and Astronomy}}, number = {{9}}, publisher = {{IOP Publishing}}, title = {{{A source of polarization-entangled photon pairs interfacing quantum memories with telecom photons}}}, doi = {{10.1088/1367-2630/16/9/093058}}, volume = {{16}}, year = {{2014}}, } @article{38095, author = {{Solntsev, Alexander S. and Setzpfandt, Frank and Clark, Alex S. and Wu, Che Wen and Collins, Matthew J. and Xiong, Chunle and Schreiber, Andreas and Katzschmann, Fabian and Eilenberger, Falk and Schiek, Roland and Sohler, Wolfgang and Mitchell, Arnan and Silberhorn, Christine and Eggleton, Benjamin J. and Pertsch, Thomas and Sukhorukov, Andrey A. and Neshev, Dragomir N. and Kivshar, Yuri S.}}, issn = {{2160-3308}}, journal = {{Physical Review X}}, keywords = {{General Physics and Astronomy}}, number = {{3}}, publisher = {{American Physical Society (APS)}}, title = {{{Generation of Nonclassical Biphoton States through Cascaded Quantum Walks on a Nonlinear Chip}}}, doi = {{10.1103/physrevx.4.031007}}, volume = {{4}}, year = {{2014}}, } @article{38092, author = {{Shayovitz, Dror and Herrmann, Harald and Sohler, Wolfgang and Ricken, Raimund and Silberhorn, Christine and Marom, Dan M.}}, issn = {{1094-4087}}, journal = {{Optics Express}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{17}}, publisher = {{The Optical Society}}, title = {{{Full-field reconstruction of ultrashort waveforms by time to space conversion interferogram analysis}}}, doi = {{10.1364/oe.22.020205}}, volume = {{22}}, year = {{2014}}, } @article{38094, author = {{Harder, G. and Mogilevtsev, D. and Korolkova, N. and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{7}}, publisher = {{American Physical Society (APS)}}, title = {{{Tomography by Noise}}}, doi = {{10.1103/physrevlett.113.070403}}, volume = {{113}}, year = {{2014}}, } @article{40952, author = {{Hamilton, Craig S. and Kruse, Regina and Sansoni, Linda and Silberhorn, Christine and Jex, Igor}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{8}}, publisher = {{American Physical Society (APS)}}, title = {{{Driven Quantum Walks}}}, doi = {{10.1103/physrevlett.113.083602}}, volume = {{113}}, year = {{2014}}, } @article{38105, author = {{Motka, L. and Stoklasa, B. and Rehacek, J. and Hradil, Z. and Karasek, V. and Mogilevtsev, D. and Harder, G. and Silberhorn, Christine and Sánchez-Soto, L. L.}}, issn = {{1050-2947}}, journal = {{Physical Review A}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{5}}, publisher = {{American Physical Society (APS)}}, title = {{{Efficient algorithm for optimizing data-pattern tomography}}}, doi = {{10.1103/physreva.89.054102}}, volume = {{89}}, year = {{2014}}, } @article{22956, abstract = {{Parametric down-conversion (PDC) forms one of the basic building blocks for quantum optical experiments. However, the intrinsic multimode spectral-temporal structure of pulsed PDC often poses a severe hindrance for the direct implementation of the heralding of pure single-photon states or, for example, continuous-variable entanglement distillation experiments. To get rid of multimode effects narrowband frequency filtering is frequently applied to achieve a single-mode behavior. A rigorous theoretical description to accurately describe the effects of filtering on PDC, however, is still missing. To date, the theoretical models of filtered PDC are rooted in the discrete-variable domain and only account for filtering in the low-gain regime, where only a few photon pairs are emitted at any single point in time. In this paper we extend these theoretical descriptions and put forward a simple model, which is able to accurately describe the effects of filtering on PDC in the continuous-variable domain. This developed straightforward theoretical framework enables us to accurately quantify the tradeoff between suppression of higher-order modes, reduced purity, and lowered Einstein–Podolsky–Rosen entanglement, when narrowband filters are applied to multimode type-II PDC.}}, author = {{Christ, Andreas and Lupo, Cosmo and Reichelt, Matthias and Meier, Torsten and Silberhorn, Christine}}, issn = {{1050-2947}}, journal = {{Physical Review A}}, number = {{2}}, title = {{{Theory of filtered type-II parametric down-conversion in the continuous-variable domain: Quantifying the impacts of filtering}}}, doi = {{10.1103/physreva.90.023823}}, volume = {{90}}, year = {{2014}}, } @article{31298, author = {{Barkhofen, Sonja and Weich, Tobias and Potzuweit, A. and Stöckmann, H.-J. and Kuhl, U. and Zworski, M.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{16}}, publisher = {{American Physical Society (APS)}}, title = {{{Experimental Observation of the Spectral Gap in Microwave n-Disk Systems}}}, doi = {{10.1103/physrevlett.110.164102}}, volume = {{110}}, year = {{2013}}, } @article{39542, author = {{Shayovitz, Dror and Herrmann, Harald and Sohler, Wolfgang and Ricken, Raimund and Silberhorn, Christine and Marom, Dan M.}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{22}}, publisher = {{The Optical Society}}, title = {{{Time-to-space conversion of ultrafast waveforms at 155  μm in a planar periodically poled lithium niobate waveguide}}}, doi = {{10.1364/ol.38.004708}}, volume = {{38}}, year = {{2013}}, }