FORMATION MECHANISM OF SELF-PUMPED PHASE-CONJUGATE MIRROR USING A CU-DOPED (K0.5NA0.5)0.2(SR0.61BA0.39)0.9NB2O6 CRYSTAL

In this work, we study the formation mechanism of the self-pumped phas e-conjugate mirror (SPPCM) in a Cu-doped (K0.5Na0.5)(0.2)(Sr0.61Ba0.39 )(0.9)Nb2O6 (KNSBN:Cu) crystal using an Ar+ laser (lambda=514 nm). The gain of self-pumped four-wave mixing is greater than that of self-gen erated fanning, which leads the self-formation of the SPPCM. The beam- fanning profiles vary with the laser beam incident angle. We observed that multiple fanning loops are formed and change with the change in i ncident angle in the SPPCM. Experimental results and discussion show t hat the transmission grating is responsible for the generation of the SPPCM. The phase-conjugate reflectivity increases with the increase in coupling constant.