Growth and characterization of Zn_xCd_(1-x)Se/Zn_(x') Cd_(y') Mg_(1-x'-y') Se asymmetric coupled quantum well structures for quantum cascade laser applications

摘要

The authors report the growth of a Ⅱ-Ⅵ Zn_xCd_(1-x)Se/Zn_(x')Cd_(y')Mg_(1-x'-y')/Se asymmetric coupled quantum well (asymmetric-CQW) structure that was used to investigate the active region of an intersubband electroluminescence structure designed for emission at λ = 4.5 μm. Such a structure could comprise the active region of a quantum cascade laser. The results of photoluminescence and Fourier transform infrared spectroscopy analysis show good agreement with the expected transition energies predicted by simulation results for the asymmetric-CQW structure. High resolution x-ray diffraction analysis indicates high structural quality of the sample and good control of the growth.