First-Principles Study of Au-Doping Effects in Hg1−xCdxTe (x = 0.25, 0.5, 0.75)
First-principles calculations based on density functional theory have been performed for the structural and electronic properties of Au-doped mercury cadmium telluride (MCT, Hg1−xCd x Te), using the state-of-the-art computational method with the Heyd-Scus-eria-Ernzerh (HSE) of hybrid functional to correct the band gap. Structural relaxations, charge densities, electron localization functions (ELFs), density of states (DOSs) and band structures were obtained to reveal dopant stability and doping efficiency. The bonding characteristics between Au and host atoms were discussed by analysing charge densities and ELFs. The influence of Cd composition on the electronic structure of Au-doped Hg1−xCd x Te (x = 0.25, 0.5, 0.75) was also analysed by the calculated DOSs and band structures. It is found that Hg0.75Cd0.25Te and Hg0.5Cd0.5Te are more suitable for the p-type doping than Hg0.25Cd0.75Te. Meanwhile, for both Hg1−xCd x Te and Au-doped Hg1−xCd x Te, the linear relationships between band gaps and Cd composition are presented.
KeywordsHg1−xCdxTe First-principles Hybrid functional Au doping Electronic structures
Project supported by National Natural Science Foundation of major research projects China (91538201), Taishan Scholar Engineering under Special Funding (ts201511020), National Science Foundation of China (61575109, 21173134, 21473103), Natural Science Foundation of Shandong Province (ZR2014FM035), and Open project of Infrared Imaging Materials and Devices Laboratory of Chinese Academy of Sciences (IIMDKFJJ-14-07).
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