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Compact cryogenic self-aligning fiber-to-detector coupling with losses below one percent



Aaron J. Miller, Adriana E. Lita, Brice R. Calkins, Igor Vayshenker, Stephen Gruber, Sae Woo Nam


We present a compact packaging technique for coupling light from a single-mode telecommunication fiber to cryogenic singlephoton sensitive devices. Our single-photon detectors are superconducting transition-edge sensors (TESs) with a collection area only a factor of a few larger than the area of the fiber core which presents significant challenges to low-loss fiber-to-detector coupling. The coupling method presented here has low loss, cryogenic compatibility, easy and reproducible assembly and low component cost. The system efficiency of the packaged single-photon counting detectors is verified by the “triplet method” of power-source calibration along with the “multiple attenuator” method that produces a calibrated single-photon flux. These calibration techniques, when used in combination with through-wafer imaging and fiber back-reflection measurements, give us confidence that we have achieved coupling losses below 1 % for all devices packaged according to the self-alignment method presented in this paper.
Optics Express


fiber-to-detector coupling, single photon detector
Created April 25, 2011, Updated February 19, 2017