Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE
Measurement of photon distribution in attenuated diode laser pulses
Liantuan Xiao, Romain Alléaume, Xuan Quyen Dinh, François Treussart, Bernard A. Journet, Jean-François Roch
Abstract
Faint laser pulses are practical signal sources in quantum key distribution. The photon statistics has been measured by recording every photo-counts moment and leading directly to the Mandel parameter of the photon distribution. Two different types operation of a single mode laser diode have been considered: either direct pulsing of the driving current or CW emission followed by pulse-shaping using an acousto-optic modulator. In both cases, it has been found that for practical attenuations, the photon distribution in each light pulse follows a poissonian statistics.