Structural and electronic properties of Pb1-xCdxTe and Pb1-xMnxTe ternary alloys

Article

关键词: TRANSPORT-PROPERTIES;    OPTICAL-PROPERTIES;    SOLID-SOLUTIONS;    CDTE;    PBTE;    BAND;    ZINCBLENDE;    CRYSTALS;   

DOI  :  10.1103/PhysRevB.86.085205

来源: SCIE

【 摘 要 】

A systematic theoretical study of two PbTe-based ternary alloys, Pb1-xCdxTe and Pb1-xMnxTe, is reported. First, using ab initio methods, we study the stability of the crystal structure of CdTe-PbTe solid solutions, to predict the composition for which the rock-salt structure of PbTe changes into the zinc-blende structure of CdTe. The dependence of the lattice parameter on Cd (Mn) content x in the mixed crystals is studied by the same methods. The obtained decrease of the lattice constant with x agrees with what is observed in both alloys. The band structures of PbTe-based ternary compounds are calculated within a tight-binding approach. To describe correctly the constituent materials, tight-binding parametrizations for PbTe and MnTe bulk crystals as well as a tight-binding description of rock-salt CdTe are proposed. For both studied ternary alloys, the calculated band gap in the L point increases with x, in qualitative agreement with photoluminescence measurements in the infrared. The results show also that in p-type Pb1-xCdxTe and Pb1-xMnxTe mixed crystals an enhancement of thermoelectrical power can be expected.

【 授权许可】

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