Anomalous Hall effect in half-metallic Heusler compound Co${}_2$Ti$X$ ($X$=Si, Ge)

Abstract

Though Weyl fermions have recently been observed in several materials with broken inversion symmetry, there are very few examples of such systems with broken time reversal symmetry. Various Co${}_2$-based half-metallic ferromagnetic Heusler compounds are lately predicted to host Weyl type excitations in their band structure. These magnetic Heusler compounds with broken time reversal symmetry are expected to show a large momentum space Berry curvature, which introduces several exotic magneto-transport properties. In this report, we present systematic analysis of experimental results on anomalous Hall effect (AHE) in Co${}_2$Ti$X$ ($X$=Si and Ge). This study is an attempt to understand the role of Berry curvature on AHE in Co${}_2$Ti$X$ family of materials. The anomalous Hall resistivity is observed to scale quadratically with the longitudinal resistivity for both the compounds. The detailed analysis indicates that in anomalous Hall conductivity, the intrinsic Karplus-Luttinger Berry phase mechanism dominates over the extrinsic skew scattering and side-jump mechanism.

References in corpus (7)

• First Principles Calculation of Anomalous Hall Conductivity in Ferromagnetic bcc Fe
• Universal Scaling Behavior of Anomalous Hall Effect and Anomalous Nernst Effect in Itinerant Ferromagnets
• Intrinsic vs. extrinsic anomalous Hall effect in ferromagnets
• Linear magnetization dependence of the intrinsic anomalous Hall effect
• Anomalous Hall effect of ferromagnetic Fe3Sn2 single crystal with geometrically frustrated kagome lattice
• Magnetotransport properties and giant anomalous Hall angle in half-Heusler compound TbPtBi
• Complex exchange mechanism driven ferromagnetism in half-metallic Heusler Co${}_2$TiGe: Evidence from critical behavior