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arXiv · 0808.3070

Near band-edge luminescence of semi-insulating undoped gallium arsenide at high levels of excitation

V. F. Kovalenko·S. V. Shutov·Ye. A. Baganov·M. M. Smyikalo
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Abstract

The dependences of the maximum and the half-width of near band-edge photoluminescence of semi-insulating undoped GaAs crystals at 77K on the concentration of background acceptor impurities and the level of excitation in the range from 3x1021 to 6x1022 quantum/(cm2/s) are investigated. The observed dependences are explained by formation of the density tails of states as a result of fluctuations of impurity concentration and participation of localized states of the donor impurity band in radiative transitions. Reduction of many-particle interaction at increasing of N can be connected with increasing of shielding of charge carriers by atoms of impurity.

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V. F. Kovalenko, S. V. Shutov, Ye. A. Baganov, M. M. Smyikalo. 2008-08-22. Near band-edge luminescence of semi-insulating undoped gallium arsenide at high levels of excitation. https://doi.org/10.1016/j.jlumin.2009.04.017

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