Solid-state lasers with a photorefractive phase-conjugate mirror

Abstract

The maintenance of high-spatial-quality radiation in laser devices as they are scaled to high powers is important for many practical applications, including laser material processing, remote sensing, and optical pumping. However, it is increasingly difficult to maintain a fundamental TEM00 high-spatial-quality mode, and a key problem in solid-state lasers is due to the onset of thermally induced refractive-index distortions in the laser amplifier. This is caused by the intensive inversion mechanism that heats the laser medium. Similarly, in high-power semiconductor diode lasers, the beam quality is severely degraded since to achieve high power (e.g., multiwatt), the emitters of the device need to be scaled to large dimensions (broad-stripe emitter) or multiple arrays of emitters must be used. The broad-stripe emitter leads to highly multimode operation and the emitter arrays are further degraded since the output radiation is spatially incoherent. © 2007 Springer.