Coexistence of tetrahedral- and octahedral-like sites in amorphous phase change materials

@article{Caravati2007CoexistenceOT,
  title={Coexistence of tetrahedral- and octahedral-like sites in amorphous phase change materials},
  author={Sebastiano Caravati and Marco Bernasconi and Thomas D. Kuehne and Matthias Krack and Michele Parrinello},
  journal={Applied Physics Letters},
  year={2007},
  volume={91},
  pages={171906}
}
Chalcogenide alloys are materials of interest for optical recording and nonvolatile memories. We perform ab initio molecular dynamics simulations aiming at shading light onto the structure of amorphous Ge2Sb2Te5 (GST), the prototypical material in this class. First principles simulations show that amorphous GST obtained by quenching from the liquid phase displays two types of short range order. One third of Ge atoms are in a tetrahedral environment while the remaining Ge, Sb, and Te atoms… Expand

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