Hong–Ou–Mandel interference between independent sources of heralded ultrafast single photons: influence of chirp
Xiaoxin Ma, Liang Cui, Xiaoying Li · Journal of the Optical Society of America B · 2015
For the quantum interference between two truly independent heralded single photon sources (HSPSs), which are generated from the spontaneous parametric processes pumping with ultrafast laser pulses, the visibility of Hong–Ou–Mandel (HOM) interference will be degraded by the mode mismatch. The mode mismatch influenced by the purity of HSPSs has been extensively investigated. Here we show that the chirp of HSPSs will change the pulse duration of ultrafast single photons and introduce additional mode mismatch. To obtain the optimized visibility, which is ultimately determined by the purity of HSPSs, the chirp of each HSPS, originated from its pulsed pump field and propagation media, should be properly managed. Our theoretical analysis shows the methods for minimizing the chirp-induced mode mismatch depend on the bandwidth and phase matching condition of the HSPSs. Our study is useful for designing the HOM interferometers in quantum information processing.