Quantum structures in Zn–Se–Te system containing submonolayer quantities of Te

Abstract

AbstractIn this paper we show that a multilayer Zn‐Se‐Te system, grown by molecular beam epitaxy in such a way as to contain sub‐monolayer quantities of Te (so‐called delta‐doped ZnSe:Te), exhibits optical properties consistent with the presence of quantum size centers. We present results of excitation intensity and temperature dependent cw photoluminescence (PL) as well as time‐resolved PL measurements that explicitly show that the ensemble of type‐II quantum islands is formed in this system. Specifically, for the 2.46–2.51 eV PL we show that (1) its maximum shifts as a cube root of excitation intensity; (2) its full‐width‐at‐half‐maximum decreases with the temperature while its maximum undergoes a red shift in the temperature interval where the integrated PL intensity stays approximately constant; (3) the PL decay is non‐exponential at high excitation intensities and a single exponential decay at low excitation intensities; (4) the PL life‐time initially increases with temperature from of 86 ns at T = 15 K to 143 ns at T = 115 K before deceasing due to non‐radiative processes. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)