QUANTUM-NOISE REDUCTION BY ELECTROOPTICAL MODULATION OF A COHERENT-LIGHT FIELD

We employ a time-dependent Hamiltonian and a time-dependent canonical transformation to investigate the possibility of reduction of quantum noise below the vacuum limit by electro-optical modulation of a coherent light field. It is shown that the amount of noise reduction depends on the time variation of the bias field in the electro-optical effect. Some illustrative examples yielding explicit results are considered, the present scenery constituting a practical realization of some theoretical models in the literature.