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Instability of the topological surface state in Bi$_2$Se$_3$ upon deposition of gold

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 نشر من قبل Matthias Geilhufe PhD
 تاريخ النشر 2018
  مجال البحث فيزياء
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Momentum resolved photoemission spectroscopy indicates the instability of the Dirac surface state upon deposition of gold on the (0001) surface of the topological insulator Bi$_2$Se$_3$. Based on the structure model derived from extended x-ray absorption fine structure experiments showing that gold atoms substitute bismuth atoms, first principles calculations provide evidence that a gap appears due to hybridization of the surface state with gold d-states near the Fermi level. Our findings provide new insights into the mechanisms affecting the stability of the surface state.



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