Electronic structure and phase stability of MgTe, ZnTe, CdTe, and their alloys in the B3, B4, and B8 structures

Ji Hui Yang, Shiyou Chen, Wan Jian Yin, X. G. Gong, Aron Walsh, Su Huai Wei

Research output: Contribution to journalArticle

48 Citations (Scopus)

Abstract

The electronic structure and phase stability of MgTe, ZnTe, and CdTe were examined in the zinc-blende (B3), wurtzite (B4), and NiAs-type (B8) crystal structures using a first-principles method. Both the band-gap and valence-band maximum (VBM) deformation potentials of MgTe, ZnTe, and CdTe in the B3 structure were analyzed, revealing a less negative band-gap deformation potential from ZnTe to MgTe to CdTe, with a VBM deformation potential increase from CdTe to ZnTe to MgTe. The natural band offsets were calculated taking into account the core-level deformation. Ternary alloy formation was explored through application of the special quasirandom structure method. The B3 structure is found to be stable over all (Zn,Cd)Te compositions, as expected from the preferences of ZnTe and CdTe. However, the (Mg,Zn)Te alloy undergoes a B3 to B4 transition above 88% Mg concentration and a B4 to B8 transition above 95% Mg concentration. For (Mg,Cd)Te, a B3 to B4 transition is predicted above 80% Mg content and a B4 to B8 transition above 90% Mg concentration. Using the calculated band-gap bowing parameters, the B3 (Mg,Zn)Te [(Mg,Cd)Te] alloys are predicted to have accessible direct band gaps in the range 2.39(1.48)-3.25(3.02) eV, suitable for photovoltaic absorbers.

Original languageEnglish
Article number245202
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume79
Issue number24
DOIs
Publication statusPublished - 2009 Jun 2

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Electronic structure and phase stability of MgTe, ZnTe, CdTe, and their alloys in the B3, B4, and B8 structures'. Together they form a unique fingerprint.

  • Cite this