Detection of resonance space-charge wave peaks for holes and electrons in photorefractive crystals

We report nonstationary photorefractive holograms in absorbing Bi(12)TiO(20) samples with different degrees of hole-electron competition exhibiting resonance peaks due to electron and hole charge carriers. One sample with moderate hole-electron competition and another with a much larger effect were studied. Experimental data from these samples were analyzed using a theoretical model accounting for electrical hole-electron coupling, wave coupling, and response-time variation along the sample thickness due to bulk light absorption. Comparing experimental data and theoretical results allows finding out material parameters adequately describing hole and electron photoactive centers in these samples. (C) 2007 Optical Society of America2461298130