We present a novel design of a superconducting nanowire single photon detectors (SNSPD) fabricated on a core of a single mode optical fiber and inside an optical cavity. We form a cavity in which light mode is confined inside the optical fiber in two dimensions, and in between fiber Bragg grating (FBG) mirror and a metallic mirror in the third dimension. The proposed new design allows resonant photonic cavity enhanced detection and high overlap between the cavity light mode and the detector. We present a theoretical model as well as preliminary experimental results. We show that by optimally tuning the system’s parameters we can set the cavity in a critical coupling condition with quantum efficiency over 98%, limited only by the absorption in the metallic mirror.

[1] arXiv:1211.1771