Temporal and spectral control of single-photon frequency upconversion for pulsed radiation

摘要

We demonstrate efficient single-photon detection at 1.04 μm with quite low background counts by using the frequency upconversion detection technique with pulsed single-photon source and strong pump field prepared from two synchronized fiber lasers. Temporal and spectral control of the pump and signal lasers enabled an upconversion efficiency of 81.1%. As the system was pumped at a wavelength longer than that of the signal, the corresponding background counts were reduced down to 1.5 × 10~3 s~(-1) due to efficient suppression of parametric fluorescence in the periodic poled lithium niobate crystal.