Optimization of the diffraction efficiency of Bi12SiO2 under strong modulation and applied electric fields

To optimize the diffraction efficiency of Bi12SiO2 we studied the influence on that efficiency of three physical parameters (thickness of the sample, applied de held, and light modulation depth m). We calculated the diffracti on efficiency by using the refractive-index variation along the thickness o f the sample and numerically solving the beam-coupling equations (for recor ding and reading). We found that for given values of m and the applied fiel d there is an optimum thickness for which the diffraction efficiency is max imum. Diffraction efficiencies of 95% were obtained for high Values of the light-modulation depth (m = 1) and strong electric fields (20 kV/cm). (C) 2 000 Optical Society of America [S0740-3224(00)02211-6] OCIS codes: 050.0050 , 050.1940.