High Efficiency Phase-Conjugate Reflection in Germanium and in Inverted CO sub 2

摘要

The first observation of phase-conjugate reflection of 10.6 mu m is reported. We used a novel intracavity technique which is of general utility for any oscillating laser system. In one experimental arrangement, we placed germanium in a TEA CO sub 2 laser cavity to utilize the intracavity counterpropagating (strong) waves for degenerate 4-wave mixing. Reflectivities as high as 20% were obtained. In a second experimental arrangement, phase-conjugate reflection and amplification with an effective gain exceeding unity was obtained by redirecting the output of a TEA CO sub 2 laser oscillator into the active gain medium. The intense counterpropagating waves within the laser medium coupled with the saturated gain medium to provide the nonlinearity in a process analogous to degenerate four-wave-mixing. (ERA citation 04:027501)