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arXiv · 2308.07380

Disorder Operator and R\'enyi Entanglement Entropy of Symmetric Mass Generation

Zi Hong Liu·Yuan Da Liao·Gaopei Pan·Menghan Song·Jiarui Zhao·Weilun Jiang·Chao-Ming Jian·Yi-Zhuang You·Fakher F. Assaad·Zi Yang Meng·Cenke Xu
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Abstract

In recent years a consensus has gradually been reached that the previously proposed deconfined quantum critical point (DQCP) for spin-1/2 systems, an archetypal example of quantum phase transition beyond the classic Landau's paradigm, actually does not correspond to a true unitary conformal field theory (CFT). In this work we carefully investigate another type of quantum phase transition supposedly beyond the similar classic paradigm, the so called ``symmetric mass generation" (SMG) transition proposed in recent years. We employ the sharp diagnosis including the scaling of disorder operator and R\'enyi entanglement entropy in large-scale lattice model quantum Monte Carlo simulations. Our results strongly suggest that the SMG transition is indeed an unconventional quantum phase transition and it should correspond to a true $(2+1)d$ unitary CFT.

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Zi Hong Liu, Yuan Da Liao, Gaopei Pan, Menghan Song, Jiarui Zhao, Weilun Jiang, Chao-Ming Jian, Yi-Zhuang You, Fakher F. Assaad, Zi Yang Meng, Cenke Xu. 2023-08-14. Disorder Operator and R\'enyi Entanglement Entropy of Symmetric Mass Generation. https://doi.org/10.1103/physrevlett.132.156503

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