Quantum frequency down-conversion of single photons at 1552 nm from single InAs quantum dot

Ma Ben^{1, 2, 3}, Wei Si-Hang^{1, 2, 3}, Chen Ze-Sheng^{1, 2, 3}, Shang Xiang-Jun^{1, 2, 3}, Ni Hai-Qiao^{1, 2, 3}, Niu Zhi-Chuan^{1, 2, 3, †}

(color online) (a) The wavelength of converted signal at 1552.29 nm calibrated by a laser at 864 nm. (b) The single-photon counting at 1552.29 nm using two SSPDs. The blue and red lines are count rates on different SSPDs and the black line is the noise background with excitation power of 140 μW. (c) The g⁽²⁾(τ) measurement of the 1552.29 nm signal under 140 μW excitation power and 308 mW pump power.