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Layered 2D crystals by design: optimisation of Sb$_2$Te$_3$-GeTe van der Waals superlattices

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 نشر من قبل Janne Kalikka
 تاريخ النشر 2015
  مجال البحث فيزياء
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Herein a genetic algorithm for optimising the design of layered 2D heterostructure is proposed. As a proof-of-concept it is applied to Sb$_2$Te$_3$-GeTe phase-change material superlattices, and the resulting lowest energy structure is grown experimentally. The similarity of the computational and experimental structures is verified with the comparison of XRD spectra. The structure is found to be within 0.92 meV/at. from the energetically most favorable known structure for Ge$_2$Sb$_2$Te$_5$.



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