Fermion-induced quantum critical points in a generalized SU(N) fermion model

The non-Landau quantum criticality dubbed as "fermion-induced quantum critical point” (FIQCP) was proposed in Ref. [1], where it was shown for 2D SU(N) Dirac fermions with N≥2. Here we investigate the nature of quantum phase transition for case of N=1. Our sign-problem-free Majorana quantum Monte Carlo simulations show that, by introducing longer-range interactions, our model exhibits transitions among Dirac semimetals, CDW, and Kekule-VBS phases. This can further provide support for the critical value of N for the occurrence of FIQCP predicted by previous RG studies.
[1] Zi-Xiang Li, Yi-Fan Jiang, Shao-Kai Jian, and Hong Yao, Fermion-induced quantum critical points, Nature Communications 8, 314 (2017)