Reducing g(2)(0) of a parametric down-conversion source via photon-number resolution with superconducting nanowire detectors
S. Sempere-Llagostera, Guillaume Thekkadath, Raj B. Patel, W. Steven Kolthammer, Ian A. Walmsley · Optics Express · 2022
Multiphoton contributions pose a significant challenge for the realisation of heralded single-photon sources (HSPS) based on nonlinear processes. In this work, we improve the quality of single photons generated in this way by harnessing the photon-number resolving (PNR) capabilities of commercial superconducting nanowire single-photon detectors (SNSPDs). We report a 13 ± 0.4% reduction of g(2)(τ = 0), even with a collection efficiency in the photon source of only 29.6%. Our work demonstrates the first application of the PNR capabilities of SNSPDs and shows improvement in the quality of an HSPS with widely available technology.