Abstract

In a recent paper,¹ it was shown that the uncertainty in the relative frequency of a two-mode laser may be eliminated by preparing the laser medium in a coherent superposition of the two upper states. Since in an active heterodyne detection scheme phase diffusion sets the ultimate limit on sensitivity, such a diffusion-free correlated, emission laser (CEL) has the potential for application in various areas of precision measurement (optical detection of rotation in particular). In a subsequent publication² the quantum theory of the CEL was developed, and an explicit expression is given there for the diffusion constant of the relative phase of the two modes. The excitation conditions in which the diffusion coefficient can vanish were derived from this general expression. It was then shown³ that CEL operation can be achieved in a ring resonator and that this arrangement is suitable for gyro application.

© 1987 Optical Society of America