Hybrid density functional study of electronic and optical properties of phase change memory material: Ge2Sb2Te5

  title={Hybrid density functional study of electronic and optical properties of phase change memory material: Ge2Sb2Te5},
  author={Thanayut Kaewmaraya and Muhammad Ramzan and 1 H. Lofaas and Rajeev Ahuja},
  journal={Journal of Applied Physics},
In this article, we use hybrid density functional (HSE06) to study the crystal and electronic structures and optical properties of well known phase change memory material Ge2Sb2Te5. We calculate the structural parameters, band gaps, and dielectric functions of three stable structures of this material. We also analyze the electron charge distribution using the Bader's theory of charge analysis. We find that hybrid density functional slightly overestimates the value of “c” parameter. However… 
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