Eu-Based Magnetic Topological Materials: Axion Insulators and Beyond
Observation of in-plane anomalous Hall effect in antiferromagnetic semimetal EuCd2Sb2
12:18 pm – 12:30 pmHall effects appearing with the presence of an out-of-plane magnetic field or magnetization have
been well studied. On the other hand, in recent years, the in-plane anomalous Hall effect which is induced by an in-plane magnetic field has been
theoretically proposed based on various different types of models1. In this work, we have
succeeded in observing large in-plane anomalous Hall effect in antiferromagnetic semimetal
EuCd2Sb2 films 2. EuCd2Sb2 has only bands forming Weyl points near the Fermi level under the
magnetic field and thus is considered to be suitable for elucidating magnetotransport phenomena
originating in the Weyl points 3. We have found that in-plane anomalous Hall resistance shows
three-fold symmetry for the field rotation on the ab-plane perpendicular to the principal c-axis
with ‘in-plane’ anomalous Hall angle of 0.2 %. Moreover, the in-plane field dependence shows
clear signals, characterized by a peak structure below the saturation field and unsaturated linear
increase even above the saturation field. This is interpreted as out-of-plane Weyl points splitting
or orbital magnetization induced by the in-plane field, while the isotropic spin magnetic moments
are fully aligned along the in-plane field direction especially in the forced ferromagnetic state.
1X. Liu et al., PRL (2013). Y. Ren et al., PRB (2016). H. Wang et al., PRL (2024). 2 A. Nakamura et al., arXiv:2403.09924. 3 M. Ohno et al., Phys. Rev. B 105, L201101 (2022), A. Nakamura et al., Phys. Rev. B 109, L121108 (2024).