학술논문
Probing the Hotspot Interaction Length in NbN Nanowire Superconducting Single-Photon Detectors
Document Type
Working Paper
Source
Subject
Language
Abstract
We measure the maximal distance at which two absorbed photons can jointly trigger a detection event in NbN nanowire superconducting single photon detector (SSPD) microbridges by comparing the one-photon and two-photon efficiency of bridges of different overall lengths, from 0 to 400 nm. We find a length of $23 \pm 2$ nm. This value is in good agreement with to size of the quasiparticle cloud at the time of the detection event.