A new comparison of photoluminescence in crystalline and amorphous arsenic triselenide (As₂Se₃)

Abstract

The accepted photoluminescence spectra of crystalline and amorphous arsenic triselenide (As₂Se₃) peak near 1·1 eV and 0·9 eV respectively. We present here new experimental results which show that the luminescence spectrum of the glass (a-As₂Se₃) depends strongly upon the excitation energy, varying in peak energy from 0·9 to 1·1 eV as the excitation energy is altered from 1·5 to 2·4 eV. By contrast, the luminescence of the crystal (c-As₂Se₃) varies little over the same range of excitation conditions. The results are compared with previously reported optically detected magnetic resonance (O.D.M.R.) data, and we discuss the implications of the present measurements for the existing models of recombination in group V-VI semiconductors.