In recent years, the demand for high power solid-state lasers in industrial and medical applications has increased. However, in high-average-power solid-state lasers, the beam quality and output efficiency are limited by thermally-induced phase and birefringence distortions. Phase conjugation is a promising technique that incorporates nonlinear optical effects to precisely reverse both the direction of propagation and phase distortion of the wave front in an arbitrary beam. By replacing one of the cavity mirrors with a phase conjugate mirror, the laser system distortions can be substantially corrected. In particular, photo refractive phase conjugation by degenerate four-wave mixing in laser media has attractive features, such as a high nonlinear efficiency. In addition, this process is capable of developing a “self-pumping” phase conjugate mirror without counter-propagating pump beams, and it is suitable for designing compact systems.
To explore a novel generation laser technology (Light-wave Synthesis) including tailor-made solid-state laser with excellent performance as high beam quality, high power, we are investigating the following projects.