Photoluminescence analysis of Cd 0.8Mn 0.2Te single crystal grown by the vertical Bridgman method

Abstract

In this paper, the photoluminescence (PL) spectra were detected to characterize Cd 0.8Mn 0.2Te crystals grown by the vertical Bridgman method. Several monocrystalline (1 1 1) face plates with dimension of 30 × 40 × 2 mm 3 were sliced from the as-grown Cd 0.8Mn 0.2Te ingot, where the PL analysis was conducted. The PL spectra revealed the neutral acceptor bound exciton (A 0, X) peaks and the donor–acceptor pair (DAP) peaks. The activation energies derived from the temperature-dependent PL quenching of the (A 0, X) peak was estimated to be 5.3 meV and 45.8 meV, which suggested the binding energy of excitons to acceptors at lower temperatures and the Auger recombination at higher temperatures. A relationship for the bandgap energy of Cd 0.8Mn 0.2Te as a function of temperature ranging from 10 K to 300 K was obtained. The composition uniformity of the (1 1 1) face Cd 0.8Mn 0.2Te plates were analyzed with PL spectra, which shown that the variation of Mn concentration is within 0.012 mole fraction.