1. Department of Physics, Peking University, Beijing 100871, China 2. Dipartimento di Fisica "A.Volta" and INFM, Università degli Studi Pavia, 27100 Pavia, Italy
Abstract：The electronic properties of Cd1-xMnxTe/CdTe semiconductor superlattices (SLs) with high Mn concentrations (x up to 0.8) were studied by means of low and room temperature photoluminescence(PL). The samples were grown by MBE on GaAs substrates with CdTe buffers. PL allowed the investigation of the optical emission from the fundamental 11H excitonic transition, revealing the high quantum efficiency and quality of the SLs. The temperature dependence of the excitonic PL energy position and excitonic line-shape broadening were studied. An exciton-longitudinal optical phonon couple model can be used to explain the experimental results very well. Photoreflectance (PR) spectra were also performed in order to compare with the authors’ photoluminescence results. The combined use of PL and PR allowed a full understanding of the electronic states and optical emission characteristics of the authors’ SLs. The authors’ results indicate that high quality Cd1-xMnxTe/CdTe SLs with high Mn concentrations can be grown using MBE on GaAs substrates. The possibility to have magnetic semiconductor nano-structures opens the way to applications in the field of spintronics toward devices based on new concepts.
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