First principles investigation of zb-TiSn: A promising narrow bandgap semiconductor

TL;DR

This study uses first principles calculations to demonstrate that zincblende TiSn is a stable, narrow bandgap semiconductor with potential optoelectronic applications, characterized by covalent bonding and specific optical properties.

Contribution

It provides the first theoretical evidence of stable zincblende TiSn as a narrow bandgap semiconductor with detailed electronic and optical properties.

Findings

zb-TiSn is a stable narrow bandgap semiconductor with a 0.3 eV gap.

The bonding in zb-TiSn is polar covalent.

Optical properties are derived from first principles calculations.

Abstract

We have investigated the structural stability of a binary compound TiSn in the zincblende symmetry. The phonon dispersion studies confirms that, TiSn with a nominal composition of 1:1 can exist in zincblende form. No imaginary frequencies are observed indicating the stable bonding nature of Ti-Sn. From the First principles calculations based on density functional theory, the resulting electronic band structure had revealed that zb-TiSn, is a narrow band gap semiconductor with an energy gap of 0.3 eV with GGA- PBE. The bonding nature is identified as polar covalent, determined from charge density difference plots and Bader charge analysis. Further more, the linear optical properties of zb-TiSn are derived from the Khon-Sham eigenvalues.