A novel superconducting single-photon detector (SSPD), intrinsically capable of high
quantum efficiency (up to 20%) over a wide spectral range (ultraviolet to infrared), with low
dark counts (< 1 cps), and fast (< 40 ps) timing resolution, is described. This SSPD has been
used to perform timing measurements on complementary metal–oxide–semiconductor
integrated circuits (ICs) by detecting the infrared light emission from switching transistors.
Measurements performed from the backside of a 0.13 μm geometry flip–chip IC are …