RUSSIAN PHYSICS JOURNAL, vol.64, no.2, pp.276-281, 2021 (SCI-Expanded)
Under various external and intracrystalline conditions (various temperatures, electric field strengths, initial values of the dark resistivity of the sample, the content and chemical nature of the introduced rare-earth impurity), the effect of a galvanically applied electric field on the intrinsic photoconductivity in single crystals of gallium selenide (p-GaSe) is studied. It is found that the photoconductivity in the samples of undoped p-GaSe single crystals with the initial dark resistivity rho(D0) <= 4 center dot 10(4) omega center dot cm at T = 77 K, as well as in the samples doped with rare earth elements (dysprosium and erbium) with a content of N-REE >= 10(-2) at.% does not depend on the electric field strength. In the samples of undoped single crystals with rho(D0)> 10(5) omega center dot cm and in the doped ones with N-REE< 10(-2) at.%, the photoconductivity depends on the electric field strength at T <= 250 K and low illumination. The observed effect of the electric field on the photoconductivity in the studied samples of p-GaSe single crystals is explained by the electric rectification of electron potential fluctuation of empty energy bands caused by the presence of random macroscopic defects in the crystals.