Electro-Optic Measurements of Single-Flux-Quantum Pulses

摘要

We report on the direct observation of a single-flux-quantum (SFQ) pulsegenerated and detected optoelectronically. With a cryogenic electro-optic sampling system, the SFQ pulse was determined to have a width of 3.2 ps, an amplitude of 0.67 mV, and a total pulse content of 2.1+/-0.2 mV.ps, corresponding to the quantum of magnetic flux h/2e. With larger excitations, multiple SFQ pulses were observed. Numerical simulations are shown to be qualitatively similar to the experimental results.