Photoluminescence of Zn_(x)Cd_(y)Mg_(1-x-y)Se alloys as a manifestation of the breakdown of 'common-anion rule'

摘要

We have systematically studied the optical properties of Zn_(x)Cd_(y)Mg_(1-x-y)Se alloys using photoluminescence (PL) and photoluminescence excitation. It is shown that, at low temperatures, PL is dominated by excitons localized by potential fluctuations, which become stronger with increasing Mg concentration. Such potential fluctuations are discussed in terms of a large valence band offset in Zn(Cd)Se/MgSe systems, which serves as a manifestation of the breakdown of "common-anion rule".