Tunable phase conjugation in a Ti:sapphire amplifier.

Four-wave mixing by gain saturation in a laser-pumped Ti:sapphire (Ti(3+):Al(2)O(3)) amplif ier is demonstrated for the f irst time to our knowledge. Small-signal gain in excess of 250 has been obtained by intense laser pumping at 532 nm, resulting in observed four-wave mixing energy ref lectivity as high as 360% for nanosecond pulses at 780 nm.