Lineshape measurement of an extreme-weak amplitude-fluctuating light source by the photon-counting-based second-order correlation spectroscopy

摘要

We demonstrate lineshape measurement of an extreme-weak amplitude fluctuatinglight source by using the photon-counting-based second-order correlationspectroscopy combined with the heterodyne technique. The amplitude fluctuationof a finite bandwidth introduces a low-lying spectral structure in thelineshape and thus its effect can be isolated from that of the phasefluctuation. Our technique provides extreme sensitivity suited forsingle-atom-level applications.