Selective two-wave mixing in photorefractive crystals

A new technique that permits the selective steady-state continuous detection of phase (photorefractive) or amplitude (photochromic) effects in two-wave mixing experiments is described. We show the capabilities of this method for the selective stabilized recording of any one of both types of grating that is chosen. Experimental results from holographic recording in Bi(12)TiO(20) are reported.