Abstract

Two extraordinary beams 1 and 2, whether coherent or incoherent entering a poled BaTiO₃ crystal on its +c face at points P and Q, to cross at R on the negative c face, generate mutually pumped phase conjugates 1 and 2 detected by D1 and D2, respectively. The beams do not self pump individually. When the gratings are formed with two coherent beams 1 and 2, and if 1 is put off, the signal D2 dies immediately while the signal D1 goes up and then decays. If, on the other hand, 1 and 2 are put off simultaneously and an incoherent beam 3 is put on in the place of 2, signal D2 dies immediately while D1 goes up for the first 11s and then decays in 40 s. This indicates formation of a Bragg grating at R responsible for beam reflection in opposite channels, and reflection gratings along paths PR and QR where beams are partially reflected backward. Thus when 1 is put off, beam 3 (or 2) goes to detector D1, which decays with gratings at R. The effective signal at D1 increases initially because of the decay of the reflection grating along PQ.

© 1992 Optical Society of America