AMPLITUDE SQUEEZING THROUGH PHOTON FRACTIONING

A prototype mechanism for producing amplitude-squeezed states, based on the so-called photon fractioning procedure, is investigated. The coherent state is connected with a quasinumber eigenstate through an intermediate density matrix involving multiphoton processes. The enhancement in the phase fluctuations and the simultaneous reduction of the noise in the photon number result from two competing limits; the bright limit, which is semiclassical and requires highly excited states, and the photon fractioning limit, which is pure quantum. Asymptotical evaluations of the number probability distribution and of the Q function show that the mixed states are very close to the exact number-phase minimum-uncertainty states. © 1990 The American Physical Society.