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arXiv · 2104.14455

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

S. K. Barman·M. N. Huda·J. Asaadi·E. Gramellini·D. Nygren
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Abstract

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 $(10\overline{1}0)$ 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 $(10\overline{1}0)$ surface slabs to access its suitability for applications as a photosensitive material.

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S. K. Barman, M. N. Huda, J. Asaadi, E. Gramellini, D. Nygren. 2021-04-29. First principles studies of the surface and opto-electronic properties of ultra-thin t-Se. https://arxiv.org/abs/2104.14455

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