Tunable Weyl fermions and Fermi arcs in magnetized topological crystalline insulators

Junwei Liu; Chen Fang; Liang Fu

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arXiv · 1604.03947

Tunable Weyl fermions and Fermi arcs in magnetized topological crystalline insulators

Junwei Liu·Chen Fang·Liang Fu

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Abstract

Based on $k\cdot p$ analysis and realistic tight-binding calculations, we find that time-reversal-breaking Weyl semimetals can be realized in magnetically-doped (Mn, Eu, Cr etc.) Sn$_{1-x}$Pb$_x$(Te,Se) class of topological crystalline insulators. All the Weyl points are well separated in momentum space and possess nearly the same energy due to high crystalline symmetry. Moreover, both the Weyl points and Fermi arcs are highly tunable by varying Pb/Sn composition, pressure, magnetization, temperature, surface potential etc., opening up the possibility of manipulating Weyl points and rewiring the Fermi arcs.

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Junwei Liu, Chen Fang, Liang Fu. 2016-04-13. Tunable Weyl fermions and Fermi arcs in magnetized topological crystalline insulators. https://arxiv.org/abs/1604.03947

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