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arXiv · 2507.23243

Disorder driven crossover between anomalous Hall regimes in Fe$_3$GaTe$_2$

Sang-Eon Lee·Minkyu Park·W. Kice Brown·Vadym Kulichenko·Yan Xin·S. H. Rhim·Chanyong Hwang·Jaeyong Kim·Gregory T. McCandless·Julia Y. Chan·Luis Balicas
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Abstract

The large anomalous Hall conductivity (AHC) of the Fe$_3$(Ge,Ga)Te$_2$ compounds has attracted considerable attention. Here, we expose the intrinsic nature of AHC in Fe$_3$GaTe$_2$ crystals characterized by high conductivities, which show disorder-independent AHC with a pronounced value $\sigma_{xy}^{\text{c}}\approx$ 420 $\Omega^{-1}$cm$^{-1}$. In the low conductivity regime, we observe the scaling relation $\sigma_{xy}\propto\sigma_{xx}^{1.6}$, which crosses over to $\sigma_{xy} \simeq \sigma_{xy}^{\text{c}}$ as $\sigma_{xx}$ increases. Disorder in low-conductivity crystals is confirmed by the broadening of a first-order transition between ferromagnetism and the ferrimagnetic ground state. Through density functional theory (DFT) calculations, we reveal that the dominant sources of Berry curvature are located a few hundred meV below the Fermi energy around the $\Gamma$-point. Therefore, Fe$_3$GaTe$_2$ clearly exposes the disorder-induced crossover among distinct AHC regimes, previously inferred from measurements on different ferromagnets located in either side of the crossover region.

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Sang-Eon Lee, Minkyu Park, W. Kice Brown, Vadym Kulichenko, Yan Xin, S. H. Rhim, Chanyong Hwang, Jaeyong Kim, Gregory T. McCandless, Julia Y. Chan, Luis Balicas. 2025-07-31. Disorder driven crossover between anomalous Hall regimes in Fe$_3$GaTe$_2$. https://doi.org/10.1103/physrevb.111.184438

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