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arXiv · 2210.06606

Electrical Seebeck-Contrast Observation of Magnon Hall Effect in Topological Ferromagnet Lu$_2$V$_2$O$_7$/Heavy Metal Heterostructures

Jinsong Xu·Jiaming He·J. -S. Zhou·Danru Qu·Ssu-Yen Huang·C. L. Chien
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Abstract

The observation of the magnon Hall effect (MHE) has relied solely on the challenging measurement of the thermal Hall conductivity. Here, we report a highly sensitive electrical Seebeck-contrast method for the observation of MHE in Lu$_2$V$_2$O$_7$/heavy metal heterostructures, that is highly desirable for the exploration of new MHE materials and their applications. Using measuring wires with very different Seebeck coefficients, we established a general method that can separate contributions (e.g., MHE) that generates a lateral temperature drop, from those [e.g., anomalous Nernst effect (ANE) and spin Seebeck effect (SSE)] that generate a lateral electric field. We show that a suitable heavy metal overlayer can eliminate the inherent ANE and SSE signals from the semiconducting Lu$_2$V$_2$O$_7$. The MHE in Lu$_2$V$_2$O$_7$ is quasi-isotropic among crystals with different orientations. In addition to the previously reported transverse MHE under an in-plane temperature gradient, we have uncovered longitudinal MHE under an out-of-plane temperature gradient.

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Jinsong Xu, Jiaming He, J. -S. Zhou, Danru Qu, Ssu-Yen Huang, C. L. Chien. 2022-10-12. Electrical Seebeck-Contrast Observation of Magnon Hall Effect in Topological Ferromagnet Lu$_2$V$_2$O$_7$/Heavy Metal Heterostructures. https://doi.org/10.1103/physrevb.109.l020401

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