Investigation of longitudinal geometry of adaptive photodetector with partially blocking contact

Longitudinal geometry for observation of transient holographic currents is investigated experimentally using thin Bi12SiO20 crystal plate with transpa rent electrodes on front and rear faces. Application of an external voltage to the uniformly illuminated structure produces nontrivial current pulse b ecause of rather complicated dynamic process of a space charge layer format ion near the partially blocking contact. If the structure under de bias is illuminated by a periodically vibrating interference pattern, the effect re sults also in an ac current component at a second harmonic of vibration fre quency. This allows us to consider this configuration as a promising one fo r adaptive detection of the optical phase modulated signals.