Enhanced anomalous Hall effect in the magnetic topological semimetal <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>Co</mml:mi><mml:msub><mml:mrow/><mml:mn>3</mml:mn></mml:msub><mml:msub><mml:mi>Sn</mml:mi><mml:mrow><mml:mn>2</mml:mn><mml:mo>−</mml:mo><mml:mi>x</mml:mi></mml:mrow></mml:msub><mml:msub><mml:mi>In</mml:mi><mml:mi>x</mml:mi></mml:msub><mml:msub><mml:mi mathvariant="normal">S</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>
Huibin Zhou, Guoqing Chang, Guangqiang Wang, Xin Gui, Xitong Xu, Jia‐Xin Yin, Zurab Guguchia, Songtian S. Zhang, Tay‐Rong Chang, Hsin Lin, Weiwei Xie, M. Zahid Hasan, Shuang Jia
Abstract
We study the anomalous Hall effect (AHE) of single-crystalline ${\mathrm{Co}}_{3}{\mathrm{Sn}}_{2\ensuremath{-}x}{\mathrm{In}}_{x}{\mathrm{S}}_{2}$ over a large range of indium concentration $x$ from 0 to 1. Their magnetization reduces progressively with increasing $x$ while their ground state evolves from a ferromagnetic Weyl semimetal into a nonmagnetic insulator. Remarkably, after systematically scaling the AHE, we find that their intrinsic anomalous Hall conductivity (AHC) features an unexpected maximum at around $x=0.15$. The change of the intrinsic AHC corresponds with the doping evolution of Berry curvature and the maximum arises from the magnetic topological nodal-ring gap. Our experimental results show a larger AHC in a fundamental nodal-ring gap than that of Weyl nodes.