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arXiv · 1604.01805

New quantum critical points of $j=3/2$ Dirac electrons in antiperovskite topological crystalline insulators

Hiroki Isobe·Liang Fu
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Abstract

We study the effect of the long-range Coulomb interaction in $j=3/2$ Dirac electrons in cubic crystals with the $O_h$ symmetry, which serves as an effective model for antiperovskite topological crystalline insulators. The renormalization group analysis reveals three fixed points that are Lorentz invariant, rotationally invariant, and $O_h$ invariant. Among them, the Lorentz- and $O_h$-invariant fixed points are stable in the low-energy limit while the rotationally invariant fixed point is unstable. The existence of a stable $O_h$-invariant fixed point of Dirac fermions with finite velocity anisotropy presents an interesting counterexample to emergent Lorentz invariance in solids.

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Hiroki Isobe, Liang Fu. 2016-06-22. New quantum critical points of $j=3/2$ Dirac electrons in antiperovskite topological crystalline insulators. https://doi.org/10.1103/physrevb.93.241113

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