  We present the characteristics of superconducting nanowire single photon
detectors (SNSPDs) fabricated from amorphous Mo0.75Ge0.25 thin-films.
Fabricated devices show a saturation of the internal detection efficiency at
temperatures below 1 K, with system dark count rates below 500 counts per
second. Operation in a Gifford-McMahon (GM) cryocooler at 2.5 K is possible
with system detection efficiencies (SDE) exceeding 20% for SNSPDs which have
not been optimized for high detection efficiency.
