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arXiv · 1906.07986

Near-room-temperature giant topological Hall effect in antiferromagnetic kagome metal YMn6Sn6

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Abstract

The kagome lattice, consisting of interconnected triangles and hexagons uniquely, is an excellent model system for study frustrated magnetism, electronic correlation and topological electronic structure. After an intensive investigation on frustrated magnetism in insulating magnetic kagome lattices, the interplay between charge and spin degrees of freedom via spin-orbital coupling in metallic systems (kagome metals) has become an attractive topic recently. Here, we study centrosymmetric YMn6Sn6 with Mn kagome lattice. We discover that it exhibits giant topological Hall effect near room temperature, ascribed to the field-induced non-collinear spin texture, possibly a skyrmion lattice (SkL) state. Combined with the large intrinsic anomalous Hall effect, YMn6Sn6 shows a synergic effect of real- and momentum-space Berry phase on physical properties. Since the features of tunable magnetic interaction and flexible structure in this large homologous series, it provides a novel platform for understanding the influence of electronic correlations on topological quantum states in both real and momentum spaces.

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Qi Wang, Qiangwei Yin, Satoru Fujitsu, Hideo Hosono, Hechang Lei. 2019-06-19. Near-room-temperature giant topological Hall effect in antiferromagnetic kagome metal YMn6Sn6. https://doi.org/10.1103/physrevb.103.014416

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