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A neural network interatomic potential for the phase change material GeTe

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 نشر من قبل Gabriele Cesare Sosso M.sc.
 تاريخ النشر 2012
  مجال البحث فيزياء
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 تأليف Gabriele C. Sosso




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GeTe is a prototypical phase change material of high interest for applications in optical and electronic non-volatile memories. We present an interatomic potential for the bulk phases of GeTe, which is created using a neural network (NN) representation of the potential-energy surface obtained from reference calculations based on density functional theory. It is demonstrated that the NN potential provides a close to ab initio quality description of a number of properties of liquid, crystalline and amorphous GeTe. The availability of a reliable classical potential allows addressing a number of issues of interest for the technological applications of phase change materials, which are presently beyond the capability of first principles molecular dynamics simulations.



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