Investigation of optoelectronic properties of half-Heusler KZnN and KZnP compounds

Abstract

This is to investigate the structural, mechanical, electronic and optical properties of half-Heusler KZnN and KZnP compounds. The ab initio method based on density functional theory is employed. The study of structural properties has allowed us to verify the cubic structure type I that is the most stable among the three possible atomic arrangements for the two half-Heusler compounds. The mechanical stability is checked, since the calculated elastic constants obey the stability criteria of cubic. Our calculations have demonstrated that KZnN is a ductile material that is considerably stiffer than KZnP, which exhibits brittleness. The obtained results for the electronic properties with mBJ-GGA approximation reveal a semiconductor behavior with a band gap along Γ as estimated at 0.3 eV and 0.9 eV for KZnN and KZnP compounds, respectively. In addition, the optical properties have been studied by analyzing the variation of different parameters such as dielectric function, refractive index, reflectivity, absorption coefficient and conductance as a function of photon’s energy for a wide range; 0 - 40 eV. The origin of peaks in the optical spectra is determined in terms of calculated energy band structures. This work has predicted strong absorption in the ultraviolet field.

Machine Learning-Based Predictions for Half-Heusler Phases

“…Half-Heusler (hH) phases continue to draw unwavering interest due to various possible applications, e.g., in optoelectronics [1,2], thermoelectric devices [1,3,4], and ferromagnets [5]. The stable hH compounds are limited to the 18 valence electron systems, i.e., ternary phases with stoichiometry of 1:1:1, XYZ (space group no F43m), where Z is a main group element, while X and Y are transition metals.…”