Anomalous transverse effects and Magneto-Optical properties of Co-based Heusler Compounds

Abstract

The interplay between magnetism and topology has brought new prospects in condensed matter physics and material science. By virtue of dissipation-free transport, a special band structure, and a greater Berry curvature, linear response in topological materials is greatly enhanced. The topological band structure in conjunction with symmetries plays a pivotal role in designing state-of-the-art materials with strong and exotic electromagnetic responses, providing favourable mechanisms for the upcoming generation of technological applications. The present work is mainly focused on an intuitive understanding of the anomalous transport coefficients and magneto-optical response in magnetic materials, particularly in regular Co-based Heusler compounds in the framework of the first-principles calculations. The ferromagnetic nature is probed through the Heisenberg exchange interactions and the Curie temperature (Tc) is estimated. With the inclusion of spin–orbit coupling in combination with non-collinear magnetization, the protective symmetries are broken consequently inducing non-vanishing valleys and peaks in the Berry curvature. The calculated values of intrinsic anomalous Hall conductivity (AHC) are 462 S/cm, 371 S/cm and 374 S/cm for the Co2HfZ (Z= Sn, Al, and Ga) and corresponding values of anomalous Nernst conductivity (ANC) are 5.6 A/m/K, −2.3 A/m/K, and 3.7 A/m/K respectively. Additionally, the magneto-optical response is also studied and the corresponding polar Kerr rotation angles at normal incidence were found to be 1.2° for Co2HfSn, 1.1° for Co2HfAl and 0.8° for Co2HfGa. Hence, this study may pave the way to scrupulous engineering of the material properties to realize the technologically desirable applications.