We have developed model that describe transformation of time modulated optical signals by the double optical and electrical interferometer: beam coupling and holographic current in the semiconductor crystals. We consider non-local response, when dominant mechanism of the space charge formation is diffusion or drift in a high external electric field.Both phase and amplitude modulation is considered (linear ramp phase modulation, sinusoidal modulation, step-like modulation). For the sinusoidal amplitude modulation slow-down of optical signal is described. Experimental results on CdTe crystal with IR CW laser (P=100mW, wavelength 1064 nm)are in agreement with theoretical predictions.Effective group velocity was slow-downed to 555 cm/s for the modulated signal with period of 8ms.

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We will describe optical and electrical effects in photorefractive materials-in semiconductors and semiconductor-ferroelectric crystals. Double-functional (optical and electrical) interferometer was realized using holographic recording of dynamic gratings in the semiconductor crystal of CdTe: V. Two mechanisms of holographic phase grating recording is considered: electro-optic effect (relatively slow, in microsecond) and free-carrier gratings {Drude-Lorentz nonlinearity, fast response in nanoseconds). Fast optical response, based on Drude-Lorentz nonlinearity (also called plasma nonlinearity) play essential role in the surface-plasmon resonance phenomena.

Double-functional (optical and electrical) interferometer was realized using holographic recording of dynamic gratings in the semiconductor crystal of CdTe:V. Two mechanisms of holographic phase grating recording is considered: electro-optic effect (relatively slow, in microsecond) and free-carrier gratings {Drude-Lorentz nonlinearity, fast response in nanoseconds).Both, electrical and optical signals from electro-optic gratings were strong enough to make direct registration on oscilloscope (without preamplifiers) using infrared (IR) CW (λ = 1064 nm) diode pumped 100 mW laser.Step-like phase modulation mimics the pulsed ultrasound modulation, used in biomedical acoustophotonic imaging. Theoretical approach is in agreement with experimental results.

Optical and electrical effects in semiconductors and ferroelectric crystals will be modeled. Standard photorefractive equations are supplemented by the equation of state for the polarization density following Devonshire-Ginsburg-Landau (DGL) approach.We have derived equations for pyroelectric and photogalvanic contribution to the holographic grating recording in ferroelectric materials. We will consider double-functional holographic interferometer, based on holographic pyroelectric current and optical beam coupling. Crystal electrostatic accelerators, based on charging of ferroelectric crystals by pyroelectric and photogalvanic effects are discussed in relation to generation of self-focused electron beam, X-rays and neutrons.