Magnetic Weyl semimetal Co₃Sn₂S₂thin flakes with high electron mobility and large anomalous Hall effect

Magnetic Weyl semimetals attract considerable interest not only for their topological quantum phenomena but also as an emerging materials class for realizing quantum anomalous Hall effect in the two-dimensional limit. In this work [1], we report a synthesis of high-quality thin flakes of magnetic Weyl semimetal Co₃Sn₂S₂ by chemical vapor transport method. In 250nm-thick thin flake, we identify the largest electron mobility (~2,600 cm²V^-1s^-1) among magnetic topological semimetals, as well as the large anomalous Hall conductivity (~1,400 Ω^-1cm^-1) and anomalous Hall angle (~32 %) arising from the Berry curvature. The enhancement of electron mobility and Berry curvature will be discussed in terms of the effective hole doping. Our study provides a viable platform for studying high-quality thin flakes of magnetic Weyl semimetal and stimulate further research on unexplored topological phenomena in the two-dimensional limit.

[1] M. Tanaka, Y. Fujishiro, M. Mogi, Y. Kaneko, T. Yokosawa, N. Kanazawa, S. Minami, T. Koretsune, R. Arita, S. Tarucha, M. Yamamoto and Y. Tokura. Nano Letters 10, 7476 (2020)