Incoherent-to-coherent IR image converter on the basis of GaAs and Bi₁₂SiO₂₀crystals

Abstract

The new model of incoherent-to-coherent infrared (IR) image converter based on a GaAs photoconductor joined to an electro-optic (EO) Bi12SiO20 crystal has been analysed theoretically and experimentally. The possibility of field transfer from the photoconductor to the EO crystal under the IR radiation sufficient for realization of the EO (Pockels) effect in the EO crystal was assessed. Based on the electric field parameters and the parameters of the photoconductor and EO crystal, the threshold sensitivity of the converter was estimated. The experimental photoconductor-EO crystal structure by which IR radiation (0.9-1.5 µm) was converted into the coherent visible radiation was obtained on the basis of theoretical calculations. The measured threshold sensitivity of the converter, 5×10-4 W cm-2, was found to be in the limits of theoretical estimation.

Memory effect in semiconductor gas discharge electronic devices

“…The experiments were carried out with the cathode plate (2) made of an SI n-type GaAs [34]. The GaAs crystal plate with a [1 0 0] surface was cut from a single-crystal ingot grown by the liquidencapsulated Czochralski method [35,36]. The diameter and the thickness of the photocathode were 36 mm and 1 mm, respectively.…”

Formation of low resistance gas state near the surface of semiconductor electrode in pre-breakdown regime

“…The ratio of the GaAs resistance in dark and under IR illumination intensity 4 × 10 −2 W cm −2 at a wavelength of λ = 1.0 µm is 10 2 . The corresponding ratio of the maximum impurity photoconductivity attributed to Cr (0.82 eV) at a wavelength of λ = 1.4 µm is 0.7 × 10 2 [22,23]. The diameter and the thickness of the photocathode are 20 mm and 1 mm, respectively.…”