3-BEAM PHASE-CONJUGATION AND MODE COMPETITION IN BATIO3

A new configuration of phase conjugation (PC) with three beams in BaTi O3 crystal is demonstrated. When two beams are incident, they can gene rate their own self-pumped PC or mutually pumped PC depending on their intensity ratio. Upon the application of a third beam, one of the two mutually pumped beams is changed into a self-pumped PC. The other for ms a double PC with the new beam. This configuration has more flexibil ity and functionality than that in the two-beam case. The analysis of mode competitions between self-pumped, mutually pumped, and double PC is given.