Study on temperature effect on properties of ZnO/MgZnO based quantum cascade detector in mid-infrared region

The effect of temperature on a ZnO/Mg0.3Zn0.7O quantum cascade detector (QCD) in the mid-infrared region is investigated with consideration of bound-to-bound electronic-transport processes in the dark and under illumination. The temperature-dependent band structures of the QCD system, which comprises four quantum wells and five barriers in one period, are numerically calculated. The electronic transition is obtained with a standard electron-optical phonon Hamiltonian, and the photon absorption is described by the two-dimensional absorption coefficient. The responsivity of the ZnO/Mg0.3Zn0.7O QCD shows a good temperature stability without an obvious redshift, and the peak responsivity decreases by only 14% when the temperature increases from 50 to 300 K. (C) 2017 The Japan Society of Applied Physics