Superconducting Nanowire Single Photon Detection System

Berggren, Anant, Baek +11 more

Francesco Marsili, Varun Boehm Verma, Jeff A. Stern +9 more

We report on a fiber-coupled eight-channel single-photon-detection system employing superconducting nanowire single-photon detectors (SNSPDs) based on amorphous tungsten silicide (WSi) with system detection efficiency ranging from 81 to 89 % at 1550 nm wavelength.

Lixing You

Miṅ Gu, Xiaolin Lin, Dongmei Liu +2 more

Superconducting nanowire single-photon detectors (SNSPDs) with a reflection grating structure are designed to enhance system detection efficiency and detection rate. The absorption capacity of the superconducting nanowires reached 92% at wavelengths of 1550 nm. It reduced the total filling factor of superconducting nanowires to only 0.25, decreased the kinetic inductance of SNSPDs, and improved the count rates.

Shigehito Miki, Taro Yamashita, Masahiro Yabuno +2 more

Nicola A. Tyler, Jorge Barreto, Gerardo E. Villarreal-Garcia +4 more

In this work we report on a single photon detector system which offers near-unity detection efficiency using waveguide-coupled superconducting nanowires with lengths on the order of 1 μm. This is achieved by embedding the nanowires in a racetrack resonator where the interaction time with the photons trapped in the cavity is increased, thereby allowing for shorter nanowires. We expect this to lead to a higher fabrication yield as the amount of inhomogeneities decreases for shorter nanowires. Our simulations show a system with a 1 μm long superconducting nanowire single photon detector (SNSPD) operating at near-unity detection efficiency using design parameters that can be realistically achieved with conventional fabrication processes. The resonant cavity introduces spectral selectivity to the otherwise broad-band SNSPDs and the cavity induced timing jitter is shown to be insignificant for SNSPDs longer than 1 μm.