@article{SetzpfandtSohlerSchieketal., author = {Setzpfandt, Frank and Sohler, Wolfgang and Schiek, Roland and Pertsch, Thomas}, title = {Nonlinear coupling in discrete optical waveguide arrays with quadratic nonlinearity}, series = {Physical Review A}, volume = {92}, journal = {Physical Review A}, number = {4}, publisher = {American Physical Society}, doi = {10.1103/PhysRevA.92.043832}, abstract = {We demonstrate nonlinear coupling in a discrete optical system. This is achieved in waveguide arrays with quadratic nonlinearity, where the symmetries of the nonlinearly interacting waveguide modes are used to suppress the usually dominating nonlinear effects within individual waveguides. We derive a mathematical model to describe the nonlinear coupling in such waveguide arrays and show experimentally the profound effects of this nonlinear coupling mechanism on second-harmonic generation.}, language = {en} } @article{SetzpfandtSolntsevTitcheneretal., author = {Setzpfandt, Frank and Solntsev, Alexander S. and Titchener, James and Wu, Che Wen and Xiong, Chunle and Schiek, Roland and Pertsch, Thomas and Neshev, Dragomir N. and Sukhorukov, Andrey A.}, title = {Tunable generation of entangled photons in a nonlinear directional coupler}, series = {Laser \& Photonics Reviews}, volume = {10}, journal = {Laser \& Photonics Reviews}, number = {1}, publisher = {WILEY-VCH}, doi = {10.1002/lpor.201500216}, pages = {131 -- 136}, abstract = {The on-chip integration of quantum light sources has enabled the realization of complex quantum photonic circuits. However, for the practical implementation of such circuits in quantum information applications, it is crucial to develop sources delivering entangled quantum photon states with on-demand tunability. Here we propose and experimentally demonstrate the concept of a widely tunable quantum light source based on spontaneous parametric down-conversion in a simple nonlinear directional coupler. We show that spatial photon-pair correlations and entanglement can be reconfigured on-demand by tuning the phase difference between the pump beams and the phase mismatch inside the structure. We experimentally demonstrate the generation of split states, robust N00N states, various intermediate regimes and biphoton steering on a single chip. Furthermore we theoretically investigate other regimes allowing all-optically tunable generation of all Bell states and flexible control of path-energy entanglement. Such wide-range capabilities of a structure comprised of just two coupled nonlinear waveguides are attributed to the intricate interplay between linear coupling and nonlinear phase matching. This scheme provides an important advance towards the realization of reconfigurable quantum circuitry.}, language = {en} } @inproceedings{SchiekSetzpfandtPertschetal., author = {Schiek, Roland and Setzpfandt, Frank and Pertsch, Thomas and Baronio, Fabio and de Angelis, Costantino}, title = {Spatial Rogue Waves in Quadratic Optical Slab Waveguides}, series = {Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF), OSA Techncail Digest (online) (Optica Publishing Group, 2018), paper NpTh1H.7}, booktitle = {Advanced Photonics 2018 (BGPP, IPR, NP, NOMA, Sensors, Networks, SPPCom, SOF), OSA Techncail Digest (online) (Optica Publishing Group, 2018), paper NpTh1H.7}, publisher = {OSA}, address = {Washington D.C.}, isbn = {978-1-943580-43-9}, doi = {10.1364/np.2018.npth1h.7}, abstract = {Spatial optical breather solutions of the Nonlinear Schr{\"o}dinger Equation have been observed for the first time. The experiment was performed in an optical slab waveguide with the cascaded quadratic nonlinearity in second-harmonic generation.}, language = {en} } @inproceedings{SetzpfandtSolntsevTitcheneretal., author = {Setzpfandt, Frank and Solntsev, Alexander S. and Titchener, James and Wu, Che W. and Xiong, Chunle and Pertsch, Thomas and Schiek, Roland and Neshev, Dragomir N. and Sukhorukov, Andrey A.}, title = {Optically tunable entangled photon state generation in a nonlinear directional coupler}, series = {CLEO: QELS_Fundamental Science 2015, San Jose, California, United States, 10-15 May 2015}, booktitle = {CLEO: QELS_Fundamental Science 2015, San Jose, California, United States, 10-15 May 2015}, publisher = {OSA}, address = {Washington, D.C.}, isbn = {978-1-55752-968-8}, doi = {10.1364/cleo_qels.2015.fth4d.3}, abstract = {We propose and experimentally demonstrate an all-optically tunable biphoton quantum light source using a nonlinear directional coupler. The source can generate high-fidelity N00N states, completely split states, and states with variable degrees of entanglement.}, language = {en} } @inproceedings{SetzpfandtSolntsevTitcheneretal., author = {Setzpfandt, Frank and Solntsev, Alexander S. and Titchener, James and Wu, Che Wen and Xiong, Chunle and Pertsch, Thomas and Schiek, Roland and Neshev, Dragomir N. and Sukhorukov, Andrey A.}, title = {Optically Tunable Entangled Photon State Generation in a Nonlinear Directional Coupler}, series = {Nonlinear Optics [Kauai, Hawaii 26-31 July 2015]}, booktitle = {Nonlinear Optics [Kauai, Hawaii 26-31 July 2015]}, number = {paper NW2A.4}, publisher = {OSA}, address = {Washington, D.C.}, isbn = {978-1-55752-001-2}, doi = {10.1364/nlo.2015.nw2a.4}, abstract = {We propose and experimentally demonstrate an all-optically tunable biphoton quantum light source using a nonlinear directional coupler. The source can generate high-fidelity N00N states, completely split states, and states with variable degrees of entanglement.}, language = {en} } @inproceedings{SetzpfandtSchiekSohleretal., author = {Setzpfandt, Frank and Schiek, Roland and Sohler, Wolfgang and Pertsch, Thomas}, title = {Nonlinear Nearest-Neighbor Coupling in Quadratic Waveguide Arrays}, series = {Nonlinear Optics : Proceedings Nonlinear Optics 26-31 July 2015, Kauai, Hawaii, United States}, booktitle = {Nonlinear Optics : Proceedings Nonlinear Optics 26-31 July 2015, Kauai, Hawaii, United States}, publisher = {OSA}, address = {Washington, D.C.}, isbn = {978-1-55752-001-2}, doi = {10.1364/nlo.2015.nm3b.6}, abstract = {We investigate nonlinear coupling between neighboring waveguides in waveguide arrays with second-order nonlinearity. Using mode symmetries to suppress local nonlinearities, we experimentally show the profound effect of such nonlinear nearest-neighbor interactions on second-harmonic generation.}, language = {en} } @inproceedings{SchiekSetzpfandtBaronio, author = {Schiek, Roland and Setzpfandt, Frank and Baronio, Fabio}, title = {Akhmediev Breathers and Modulation Instability's Growth-Decay Cycle in Slab Waveguides}, series = {Nonlinear Optics : 15-19 July 2019, Waikoloa Beach, Hawaii, United States}, booktitle = {Nonlinear Optics : 15-19 July 2019, Waikoloa Beach, Hawaii, United States}, publisher = {OSA}, address = {Washington, D.C.}, isbn = {978-1-943580-62-0}, doi = {10.1364/nlo.2019.ntu2a.2}, abstract = {Optical film waveguides served as new platform for investigating Akhmediev Breathers. Using the interplay between third-order and cascaded second-order optical nonlinearities breathers and modulation instability cycles in a wide nonlinear regime were characterized.}, language = {en} }