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First principles studies of the surface and opto-electronic properties of ultra-thin t-Se

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 نشر من قبل Jonathan Asaadi
 تاريخ النشر 2021
  مجال البحث فيزياء
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Selenium is a crucial earth-abundant and non-toxic semiconductor with a wide range of applications across the semiconductor industries. Selenium has drawn attention from scientific communities for its wide range of applicability: from photovoltaics to imaging devices. Its usage as a photosensitive material largely involves the synthesis of the amorphous phase (a-Se) via various experimental techniques. However, the ground state crystalline phase of this material, known as the trigonal selenium (textit{t}-Se), is not extensively studied for its optimum electronic and optical properties. In this work, we present density functional theory (DFT) based systematic studies on the ultra-thin $(10overline{1}0)$ surface slabs of textit{t}-Se. We report the surface energies, work function, electronic and optical properties as a function of number of layers for $(10overline{1}0)$ surface slabs to access its suitability for applications as a photosensitive material.



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