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arXiv · 2310.03009

Electronic structure evolution of the magnetic Weyl semimetal Co$_3$Sn$_2$S$_2$ with hole and electron doping

Himanshu Lohani·Paul Foulquier·Patrick Le Fevre·Francois Bertran·Dorothee Colson·Anne Forget·Veronique Brouet
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Abstract

Co$_3$Sn$_2$S$_2$ has been established as a prototype of magnetic Weyl semimetal, exhibiting a ''giant'' anomalous Hall effect in its ferromagnetic phase. An attractive feature of this material is that Weyl points lie close to Fermi level, so that one can expect a high reactivity of the topological properties to hole or electron doping. We present here a direct observation with Angle Resolved Photoemission Spectroscopy of the evolution of the electronic structure under different types of substitutions : In for Sn (hole doping outside the kagome Co plane), Fe for Co (hole doping inside the kagome Co plane) and Ni for Co (electron doping inside the kagome Co plane). We observe clear shifts of selected bands, which are due both to doping and to the reduction of the magnetic splitting by doping. We discriminate between the two by studying the temperature evolution from ferromagnetic to paramagnetic state. We discuss these shifts with the help of DFT calculations using the Virtual Crystal Approximation. We find that these calculations reproduce rather well the evolution with In, but largely fail to capture the effect of Fe and Ni, where local behavior at the impurity site plays an important role.

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Himanshu Lohani, Paul Foulquier, Patrick Le Fevre, Francois Bertran, Dorothee Colson, Anne Forget, Veronique Brouet. 2023-10-04. Electronic structure evolution of the magnetic Weyl semimetal Co$_3$Sn$_2$S$_2$ with hole and electron doping. https://doi.org/10.1103/physrevb.107.245119

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