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arXiv · 0908.1324

Nonlinear Hall effect as a signature of electronic phase separation in the semimetallic ferromagnet EuB6

Xiaohang Zhang·Liuqi Yu·Stephan von Molnar·Zachary Fisk·Peng Xiong
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Abstract

This work reports a study of the nonlinear Hall Effect (HE) in the semimetallic ferromagnet EuB6. A distinct switch in its Hall resistivity slope is observed in the paramagnetic phase, which occurs at a single critical magnetization over a wide temperature range. The observation is interpreted as the point of percolation for entities of a more conducting and magnetically ordered phase in a less ordered background. With an increasing applied magnetic field, the conducting regions either increase in number or expand beyond the percolation limit, hence increasing the global conductivity and effective carrier density. An empirical two-component model expression provides excellent scaling and a quantitative fit to the HE data and may be applicable to other correlated electron systems.

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Xiaohang Zhang, Liuqi Yu, Stephan von Molnar, Zachary Fisk, Peng Xiong. 2009-08-10. Nonlinear Hall effect as a signature of electronic phase separation in the semimetallic ferromagnet EuB6. https://doi.org/10.1103/physrevlett.103.106602

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