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arXiv · 2212.11821

Fermion disorder operator at Gross-Neveu and deconfined quantum criticalities

Zi Hong Liu·Weilun Jiang·Bin-Bin Chen·Junchen Rong·Meng Cheng·Kai Sun·Zi Yang Meng·Fakher F. Assaad
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Abstract

The fermion disorder operator has been shown to reveal the entanglement information in 1D Luttinger liquids and 2D free and interacting Fermi and non-Fermi liquids emerging at quantum critical points(QCP). Here we study, by means of large-scale quantum Monte Carlo simulation, the scaling behavior of disorder operator in correlated Dirac systems. We first demonstrate the logarithmic scaling behavior of the disorder operator at the Gross-Neveu (GN) chiral Ising and Heisenberg QCPs, where consistent conformal field theory (CFT) content of the GN-QCP in its coefficient is found. Then we study a 2D monopole free deconfined quantum critical point (DQCP) realized between a quantum-spin Hall insulator and a superconductor. Our data point to negative values of the logarithmic coefficients such that the DQCP does not correspond to a unitary CFT. Density matrix renormalization group calculations of the disorder operator on a 1D DQCP model also detect emergent continuous symmetries.

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Zi Hong Liu, Weilun Jiang, Bin-Bin Chen, Junchen Rong, Meng Cheng, Kai Sun, Zi Yang Meng, Fakher F. Assaad. 2022-12-22. Fermion disorder operator at Gross-Neveu and deconfined quantum criticalities. https://doi.org/10.1103/physrevlett.130.266501

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