Superconducting nanowire single-photon detectors : new detector architectures and integration with photonic chips

Thesis: Ph. D., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2015.Cataloged from PDF version of thesis.Includes bibliographical references (pages 153-161).Superconducting nanowire single-photon detectors (SNSPDs) are a promising technology for long-distance optical communication and quantum information processing. Recent advances in single-photon generation, storage and detection technologies have spurred interest in integration of these components onto a single microchip, which would act as a low-power non-classical optical processor. In this thesis, I will present a method for the scalable integration of SNSPDs with photonic chips. I will show that, using a micron-scale flip-chip process, waveguide-coupled SNSPDs can be integrated onto a variety of material systems with high yield. This technology enabled the assembly of the first photonic chip with multiple adjacent SNSPDs with average system detection efficiencies beyond 10%. Using this prototype, we will show the first on-chip detection of non-classical light. I will further demonstrate optimizations to the detector design and fabrication processes. These optimizations increased the direct fabrication yield and improved the timing jitter to 24 ps for detectors with high internal efficiency. Furthermore, I will show a novel single-photon detector design that may have the potential to reach photodetection dead times below 1ns.by Faraz Najafi.Ph. D