Chemical-substitution-driven giant anomalous Hall and Nernst effects in magnetic cubic Heusler compounds

TL;DR

This study uses high-throughput first-principles calculations to show how chemical substitution in magnetic cubic Heusler compounds can significantly enhance anomalous Hall and Nernst effects, revealing promising candidates for advanced spintronic applications.

Contribution

It systematically demonstrates the impact of chemical substitution on AHC and ANC in 1493 Heusler compounds, identifying specific substitutions that lead to record-high transport properties.

Findings

Certain substitutions greatly increase AHC and ANC values.

Identification of compounds with record-high AHC and ANC.

Enhanced ANC linked to creation of energy-dependent nodal lines.

Abstract

Chemical substitution efficiently optimizes the physical properties of Heusler compounds, especially their anomalous transport properties, including anomalous Hall conductivity (AHC) and anomalous Nernst conductivity (ANC). This study systematically investigates the effect of chemical substitution on AHC and ANC in 1493 magnetic cubic Heusler compounds using high-throughput first-principles calculations. Notable trends emerge in Co- and Rh-based compounds, where chemical substitution effectively enhances the AHC and ANC. Intriguingly, certain chemically substituted candidates exhibit outstanding enhancement in AHCs and ANCs, such as (Co$_{0.8}$Ni$_{0.2}$)$_2$FeSn with considerable AHC and ANC values of $-2567.78$ S cm$^{-1}$ and $8.27$ A m$^{-1}$K$^{-1}$, respectively, and (Rh$_{0.8}$Ru$_{0.2}$)$_2$MnIn with an AHC of $1950.49$ S cm$^{-1}$. In particular, an extraordinary ANC of $8.57$ A m$^{-1}$K$^{-1}$ is identified exclusively in Rh$_2$Co$_{0.7}$Fe$_{0.3}$In, nearly double the maximum value of $4.36$ A m$^{-1}$K$^{-1}$ observed in the stoichiometric Rh$_2$CoIn. A comprehensive band structure analysis underscores that the notable enhancement in ANC arises from the creation and modification of the energy-dependent nodal lines through chemical substitution. This mechanism generates a robust Berry curvature, resulting in significant ANCs. These findings emphasize the pivotal role of chemical substitution in engineering high-performance materials, thereby expanding the horizons of transport property optimization within Heusler compounds.