Abstract

There has recently been considerable interest in phase-conjugate oscillators (PCOs). In particular, several Nd:YAG-based pulsed configurations have been reported in which a stimulated Brillouin scattering cell functioned as the phase-conjugate mirror.^1–3 Preliminary experiments in our laboratory have indicated that such a PCO is essentially as efficient as a conventional oscillator. This is somewhat surprising in view of speculations⁴ that accumulated SBS shifts might prematurely terminate the lasing process by walking the radiation out of the Nd:YAG gain bandwidth. One possible explanation is that some other stimulated scattering process having a smaller frequency shift⁵ might be operating, thereby eliminating any significant frequency walk-off. To clarify this matter, we investigated the spectrum of such a PCO, presenting here what is to our knowledge the first quantitative data showing Brillouin-shifted sidelobes on a broadened⁶ phase-conjugate resonator spectrum.

© 1986 Optical Society of America