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arXiv · 1705.09192

Dynamical Generation of Topological Masses in Dirac Fermions

Yuan-Yao He·Xiao Yan Xu·Kai Sun·Fakher F. Assaad·Zi Yang Meng·Zhong-Yi Lu
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Abstract

We report discovery of a topological Mott insulator in strongly-correlated Dirac semimetals. Such an interaction-driven topological state has been theoretically proposed but not yet observed with unbiased large scale numerical simulations. In our model, interactions between electrons are mediated by Ising spins in a transverse field. The results indicate that the topological mass term is dynamically generated and the resulting quantum phase transition belongs to the (2+1)D $N=8$ chiral Ising universality class. These conclusions stem from large scale sign free quantum Monte Carlo simulations.

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Yuan-Yao He, Xiao Yan Xu, Kai Sun, Fakher F. Assaad, Zi Yang Meng, Zhong-Yi Lu. 2017-06-03. Dynamical Generation of Topological Masses in Dirac Fermions. https://doi.org/10.1103/physrevb.97.081110

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