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arXiv · 1708.02538

Large Spontaneous Hall Effects in Chiral Topological Magnets

S. Nakatsuji·T. Higo·M. Ikhlas·T. Tomita·Z. Tian
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Abstract

As novel topological phases in correlated electron systems, we have found two examples of non-ferromagnetic states that exhibit a large anomalous Hall effect. One is the chiral spin liquid compound Pr$_{2}$Ir$_{2}$O$_{7}$, which exhibits a spontaneous Hall effect in a spin liquid state due to spin ice correlation. The other is the chiral antiferromagnets Mn$_{3}$Sn and Mn$_{3}$Ge that exhibit a large anomalous Hall effect at room temperature. The latter shows a sign change of the anomalous Hall effect by a small change in the magnetic field by a few 100 G, which should be useful for various applications. We will discuss that the magnetic Weyl metal states are the origin for such a large anomalous Hall effect observed in both the spin liquid and antiferromagnet that possess almost no magnetization.

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S. Nakatsuji, T. Higo, M. Ikhlas, T. Tomita, Z. Tian. 2017-08-08. Large Spontaneous Hall Effects in Chiral Topological Magnets. https://doi.org/10.1080/14786435.2017.1352106

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