Specular reflection cancellation in an interferometer with a phase-conjugate mirror

Abstract
An ordinary mirror placed in front of a phase-conjugate mirror forms a type of Fabry–Perot interferometer with unusual reflection properties. The specularly reflected and phase-conjugate reflected intensities are analyzed for arbitrary reflection coefficients, given an incident monochromatic linearly polarized plane wave. It is shown that if the ordinary mirror is lossless and the phase-conjugate reflectivity is unity, the specularly reflected wave disappears completely. This leaves only the phase-conjugate reflected wave that propagates in the direction opposite to that of the incident wave. The above result is independent of the reflectivity of the ordinary mirror and the separation between the two interferometer mirrors. Some of the main effects due to absorption in the ordinary mirror are briefly discussed.