Integrated photonic quantum information processing (QIP) has advanced rapidly due to progress in various nanophotonic platforms. Single-photon detectors have been the subject of intense study due to their ubiquity in QIP systems, yet many detectors operate at cryogenic temperatures under vacuum and are limited in operating speed by their dead times. We propose and characterize an all-optical single-photon detection scheme based on optical parametric amplification in nanophotonic lithium niobate (LN) combined with a macroscopic photodetector. We use quantum detector tomography and experimentally determine the positive operator-valued measure of the detector. The detector operates at room temperature at a count rate of 250 MHz and is readily integrated in LN nanophotonics. While the demonstrated experimental performance falls short of existing photon detectors, we show that in the future, by improving the nonlinearity-to-loss ratio and using homodyne detection on a squeezed pump, the detector can achieve a performance sufficient to create non-Gaussian states, such as Schrödinger’s cat states. Our results highlight a path toward all-optical photon detection for scalable high-throughput nanophotonic quantum communication and information processing.

Close

PrevNext

View figure in article

• Integrated optics
• Nanophotonics
• Nonlinear waveguides
• Optical quantum information processing
• Nonlinear optical materials
• Optical parametric oscillators & amplifiers
• Optical sources & detectors
• Single-photon detectors