The spread of cross section for electron capture by a trap with a discreteenergy level in gamma-La2S3 crystals

The data on a new phenomenon (a formation of the range of values for an ele ctron-capture cross section) are reported by the example of an electron tra p with a discrete level of E-c - 0.2 eV in gamma -La2S3 crystals; the data were obtained by employing the thermally stimulated luminescence. The range of variations in the cross section is as large as four orders of magnitude (10(-23)-10(-19) cm(2)). A model, according to which the electron trap at E-c - 0.2 eV is a donor involved in the donor-acceptor pairs distributed in interatomic distances and localized in the vicinity of a negatively charge d dislocation, is suggested. It is shown that the formation of a range of e lectron-capture cross sections is a result of a spread of the cross-section modulation factor at points with different values of potential of the disl ocation electric field. (C) 2001 MAIK "Nauka/Interperiodica".