Performance of a continuous-wave self-adaptive gain-grating laser

Summary form only given. Experimental and theoretical studies have shown that three-dimensional gain gratings, optically written in a saturable laser amplifier, can act as very efficient (>1000%) diffractive optical elements and, in a four-wave mixing (FWM) geometry, can produce extremely high phase-conjugate reflectivity. A further development in the use of gain gratings for phase conjugation has been the employment of loop schemes to obtain self-pumped phase conjugation (SPPC) with only one input beam required. In reality, these devices are actually a novel type of (holographic) laser where the feedback is provided by diffraction from an externally-written gain-grating hologram.