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Three Non-Steady-State Photo-EMF Excitation Modes in a Gallium Oxide Crystal


This paper presents the results of measurements of the non-steady-state photo-emf in a monoclinic Ga2O3 crystal at a laser wavelength of 457 nm. The crystal has insulating properties and shows high transparency for visible light, which does not prevent the formation of the dynamic space-charge grating and non-steady-state photo-emf signal recording in external (null, dc, and ac) electric fields. The measured signal amplitude is analyzed as a function of the phase modulation frequency, spatial frequency of the interference pattern, and the electric field. The crystal photoconductivity, spectral sensitivity, and diffusion length of photoexcited carriers are determined for the chosen wavelength.

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The study was supported by the Russian Science Foundation (project no. 19-12-00323).

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Correspondence to I. A. Sokolov.

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The authors declare that they have no conflicts of interest.

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Translated by A. Kazantsev

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Bryushinin, M.A., Sokolov, I.A., Zavestovskaya, I.N. et al. Three Non-Steady-State Photo-EMF Excitation Modes in a Gallium Oxide Crystal. Bull. Lebedev Phys. Inst. 49, 67–73 (2022).

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  • non-steady-state photo-emf
  • adaptive photodetector