Canting-induced anomalous Hall effect in RGaGe (R <b>=</b> Nd, Gd) single crystals

Abstract

Recently, the non-centrosymmetric Weyl semimetallic candidate family RTX (R = rare-earth element, T = poor metal, X = Si and Ge) has recently attracted significant attention due to its exotic quantum states and potential applications in quantum devices. In this study, our comprehensive investigations of high-quality NdGaGe and GdGaGe single crystals reveal distinct magnetic and electrical responses. Both compounds exhibit antiferromagnetic transitions with TN ∼ 7.6 and 22.4 K for NdGaGe and GdGaGe, respectively. NdGaGe exhibits strong magnetic anisotropy (χc/χa ∼ 70). In contrast, GdGaGe displays weak magnetic anisotropic behavior (χc/χa ∼ 1) with a distinctive spin-flop transition. Below TN, NdGaGe shows significant negative magnetoresistance due to the reduced spin-disorder scattering arising from the field-induced spin alignment. GdGaGe exhibits more complex magnetoresistance behavior: positive values at low fields transitioning to negative values attributed to the reduced spin-flop scattering. Specifically, NdGaGe demonstrates a large anomalous Hall conductance (AHC) of approximately 368 Ω−1 cm−1, which is dominated by the intrinsic mechanism. These results reveal the pivotal role of rare-earth elements in modulating the electronic structure, magnetic properties, and transport characteristics of the RGaGe system, thereby providing valuable insights for developing next-generation spintronic devices.