Abstract

A near-number state features strongly sub-Poissonian photon-number fluctuation and, unlike a quadrature squeezed state, the photonnumber noise can approach zero, with a finite average photon number. It is now well established that a beam with a sub-Poissonian photon-number fluctuation can be generated directly from a semiconductor laser,^l,2 The basic physical processes are a) quantum mechanical interference between the transmitted internal field and the reflected vacuum field at the output coupler and b) high impedance suppression of the pump noise.

© 1991 Optical Society of America