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arXiv · 1603.08376

Quantum critical point of Dirac fermion mass generation without spontaneous symmetry breaking

Yuan-Yao He·Han-Qing Wu·Yi-Zhuang You·Cenke Xu·Zi Yang Meng·Zhong-Yi Lu
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Abstract

We study a lattice model of interacting Dirac fermions in $(2+1)$ dimension space-time with an SU(4) symmetry. While increasing interaction strength, this model undergoes a {\it continuous} quantum phase transition from the weakly interacting Dirac semimetal to a fully gapped and nondegenerate phase without condensing any Dirac fermion bilinear mass operator. This unusual mechanism for mass generation is consistent with recent studies of interacting topological insulators/superconductors, and also consistent with recent progresses in lattice QCD community.

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Yuan-Yao He, Han-Qing Wu, Yi-Zhuang You, Cenke Xu, Zi Yang Meng, Zhong-Yi Lu. 2016-03-28. Quantum critical point of Dirac fermion mass generation without spontaneous symmetry breaking. https://doi.org/10.1103/physrevb.94.241111

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