First-principles study of anomalous Hall effect and anomalous Nernst effect in Fe2Si

Abstract

We have performed density functional calculations of the electronic structure, anomalous Hall conductivity, and anomalous Nernst conductivity for the model crystal structure of a mineral Hapkeite Fe2Si contained in a meteorite Dhofar 280, which is believed to originate from the Moon. The calculated results showed that the model structure of Hapkeite Fe2Si exhibits a larger transverse thermoelectric effect than bcc-Fe and hexagonal Fe2Si. Based on the detailed analysis of the electronic structures and transport coefficients, we found that the origin of the large transverse thermoelectric effect is due to an anomaly in the density of states at the interface between the Fe layers and the Si–Fe alternative stacked layers. This finding is promising for the design of new transverse thermoelectric materials.