Superconducting nanowire single photon detectors for infrared communications

Chandra M. Natarajan, Martin M. Härtig, Ryan E. Warburton +8 more

Q. Wang, J. J. Renema, Andreas Engel +1 more

Superconducting nanowire single-photon detectors (SNSPDs) are important in quantum optics, secure communication, and even medical imaging. An SNSPD exhibits higher detection efficiency when a photon is absorbed near the edge of its wire, rather than in the middle. Combining insight from superconductor physics with nanophotonics, the authors show how to concentrate incident light on the edges of the nanowire, to enhance the efficiency and speed of next-generation detectors. This is expected to be particularly useful in the infrared range, for which there is presently no alternative SPD technology.

Matthew D. Shaw

Superconducting Nanowire Single Photon Detectors (SNSPDs) are the most advanced detectors available for time-resolved single photon counting from the UV to the mid-infrared. We will discuss recent progress in SNSPD development for the ground terminal in NASA’s Deep Space Optical Communication (DSOC) project as well as recent performance advances in other metrics, including the development of kilopixel SNSPD arrays, single-photon sensitivity at mid-infrared wavelengths as long as 10 microns, and SNSPDs with sub-3ps timing jitter. I will discuss a range of new potential scientific applications for SNSPDs, including exoplanet transit spectroscopy, dark matter detection, fluorescence lifetime imaging microscopy, and quantum information science.

Berggren, Anant, Baek +11 more

Francesco Bellei, Alyssa P. Cartwright, Adam N. McCaughan +4 more

This paper describes the construction of a cryostat and an optical system with a free-space coupling efficiency of 56.5% ± 3.4% to a superconducting nanowire single-photon detector (SNSPD) for infrared quantum communication and spectrum analysis. A 1K pot decreases the base temperature to T = 1.7 K from the 2.9 K reached by the cold head cooled by a pulse-tube cryocooler. The minimum spot size coupled to the detector chip was 6.6 ± 0.11 µm starting from a fiber source at wavelength, λ = 1.55 µm. We demonstrated photon counting on a detector with an 8 × 7.3 µm2 area. We measured a dark count rate of 95 ± 3.35 kcps and a system detection efficiency of 1.64% ± 0.13%. We explain the key steps that are required to improve further the coupling efficiency.

Matt Shaw, Francesco Marsili, Andrew D. Beyer +9 more