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arXiv · 1909.09580

Magnetic Weyl Semimetal Phase in a Kagome Crystal

D. F. Liu·A. J. Liang·E. K. Liu·Q. N. Xu·Y. W. Li·C. Chen·D. Pei·W. J. Shi·S. K. Mo·P. Dudin·T. Kim·C. Cacho·G. Li·Y. Sun·L. X. Yang·Z. K. Liu·S. S. P. Parkin·C. Felser·Y. L. Chen
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Abstract

Weyl semimetals are crystalline solids that host emergent relativistic Weyl fermions and have characteristic surface Fermi-arcs in their electronic structure. Weyl semimetals with broken time reversal symmetry are difficult to identify unambiguously. In this work, using angle-resolved photoemission spectroscopy, we visualized the electronic structure of the ferromagnetic crystal Co3Sn2S2 and discovered its characteristic surface Fermi-arcs and linear bulk band dispersions across the Weyl points. These results establish Co3Sn2S2 as a magnetic Weyl semimetal that may serve as a platform for realizing phenomena such as chiral magnetic effects, unusually large anomalous Hall effect and quantum anomalous Hall effect.

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D. F. Liu, A. J. Liang, E. K. Liu, Q. N. Xu, Y. W. Li, C. Chen, D. Pei, W. J. Shi, S. K. Mo, P. Dudin, T. Kim, C. Cacho, G. Li, Y. Sun, L. X. Yang, Z. K. Liu, S. S. P. Parkin, C. Felser, Y. L. Chen. 2019-09-20. Magnetic Weyl Semimetal Phase in a Kagome Crystal. https://doi.org/10.1126/science.aav2873

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