Hy-Q Seminar - Emma Lomonte - University of Münster
Meeting ID: 626 998 5606
Title: Single-photon detection and cryogenic reconfigurability in lithium niobate nanophotonic circuits
Abstract: Lithium-Niobate-On-Insulator (LNOI) has recently emerged as a promising platform for integrated quantum photonic technologies thanks to its wide transparency range, high second-order nonlinearity, and compact waveguide footprint. Importantly, LNOI allows for the realization of electro-optically reconfigurable circuits, which can be efficiently operated at cryogenic temperature. Their integration with superconducting nanowire single-photon detectors (SNSPDs) paves the way for realizing scalable photonic devices for active manipulation and detection of quantum states of light. By means of a specially tailored fabrication process, here we report the monolithic integration of these two key components in a single low loss LNOI device. As an experimental showcase of our technology, we demonstrate the combined operation of an electrically tunable Mach-Zehnder interferometer and two waveguide-integrated SNSPDs at its outputs. We show static reconfigurability of our system with a bias-drift-free operation over a time of 12 hours, as well as high-speed modulation at a frequency up to 1 GHz.