Optoelectronic and transport properties of Fe2TiGe with the Tran-Blaha modified Becke-Johnson potential

TL;DR

This study uses first principles calculations to analyze the optoelectronic, thermodynamic, and transport properties of Fe2TiGe, revealing its potential for optical and photovoltaic applications due to its semiconductor nature and optical characteristics.

Contribution

The paper applies the Tran-Blaha modified Becke-Johnson potential in DFT calculations to comprehensively characterize Fe2TiGe's properties, highlighting its suitability for optoelectronic devices.

Findings

Fe2TiGe is an indirect band gap semiconductor with a 0.734 eV gap.

High absorption coefficient in the ultraviolet region.

Potential use in optical devices and photovoltaic applications.

Abstract

In this paper, we have performed first principles calculations to study optoelectronic, thermodynamic and transport properties of Fe2TiGe using density functional theory (DFT). The semi-classical Boltzmann transport theory is used to investigate transport properties. The calculated energy bands indicate that Fe2TiGe is an indirect band gap semiconductor with band gap 0.734 eV for TB-mBJ functional. Fe-3d and Ti-3d orbitals have the dominant contributions to the density of states due to strong hybridization between them. The maximum value of absorption coefficient is found to be 224x10^4 cm-1 in the ultraviolet region. It is found that the static refractive index of Fe2TiGe is 5.18 which is very close to that of Ge and much higher than that of GaAs. The obtained refractive index implies that Fe2TiGe is a potential optical material that can be used in optical devices such as photonic crystal, wave guides and solar cells. The Debye temperature at ambient condition is 570 K and decreases slowly with temperature. The Gruneisen parameter at ambient pressure and 300 K is 2.1 and slightly higher than that of PbTe (1.5). The calculated Seebeck coefficient and power factor at 300 K using TB-mBJ functional are 271x10^-6 VK^-1 and 5.9x10^10 Wcm^-1K^-2, respectively. Therefore, the calculated optoelectronic properties implies that Fe2TiGe is a potential candidate for photovoltaic device applications.