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In work are investigated particularities of photoelectric properties of GaSe monocrystals in the region of absorption edge at various configurations of current contacts at low and high optical excitation levels. It is established, that the form of a spectrum of photoconductivity in the region of absorption edge is determined by two factors: by localization electronic and exciton states along c-axis, due to presence defects of packing and nonlinear light absorption at high excitation levels in the exciton absorption region. It is shown, that the localization of electronic state and excitons in the field of one_dimensional fluctuation potential along c_axis results to an anisotropy of spectrum of photoconductivity at various configurations of current contacts. At EƒÎc the photoconductivity is observed as in the region hν< Eg , and in the region hμ≥ Eg . And at hν< the photoconductivity as in impurity absorption region with energy of a maximum 1.960/1.975 eV, and in exciton absorption region with energy of a maximum 2.0 eV are observed. With rise of level excitation is observed suppressions of photoconductivity in the exciton absorption region and increasing in impurity absorption region. At E || c the considerable photoconductivity is observed only in the region impurity absorption, which also is increased with rise of level excitation. It is supposed, that suppression of photoconductivity in the exiton absorption at high levels of excitation is connected with exiton_exciton interaction, which results in a nonlinear light absorption. |