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

Abstract

Selenium is an important earth-abundant and non-toxic semiconductor with numerous applications across the semiconductor industries. Selenium has drawn attention from scientific communities for photovoltaics and 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 (t-Se), has not been extensively studied for its optimum electronic and optical properties. In this work, we present systematic studies based on density functional theory (DFT) for ultra-thin (1010) surface slabs of t-Se. We report the surface energies, work function, electronic and optical properties as a function of number of layers for (1010) surface slabs to access its suitability for applications as a photosensitive material.