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Fermion Disorder Operator at Gross-Neveu and Deconfined Quantum Criticalities.
Zi Hong Liu1, Weilun Jiang2,3, Bin-Bin Chen4
1Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, 97074 Würzburg, Germany.
Physical Review Letters
|July 14, 2023
Summary
We investigated the disorder operator
Area of Science:
- Condensed Matter Physics
- Quantum Field Theory
Background:
- The fermion disorder operator reveals entanglement in 1D Luttinger liquids and 2D Fermi/non-Fermi liquids at quantum critical points (QCPs).
- Understanding disorder operator scaling is crucial for characterizing QCPs.
Purpose of the Study:
- To investigate the scaling behavior of the disorder operator in correlated Dirac systems using large-scale quantum Monte Carlo simulations.
- To analyze the conformal field theory (CFT) content of Gross-Neveu quantum critical points (QCPs).
- To study deconfined quantum critical points (DQCPs) between quantum-spin Hall insulators and superconductors.
Main Methods:
- Large-scale quantum Monte Carlo simulations.
- Density matrix renormalization group (DMRG) calculations.
- Analysis of logarithmic scaling behavior.
Main Results:
- Logarithmic scaling of the disorder operator was demonstrated at Gross-Neveu (GN) chiral Ising and Heisenberg QCPs, consistent with CFT predictions.
- Negative logarithmic coefficients were found for a 2D deconfined quantum critical point (DQCP), suggesting it is not a unitary CFT.
- DMRG calculations on a 1D DQCP model revealed emergent continuous symmetries.
Conclusions:
- The disorder operator provides insights into the nature of QCPs and DQCPs.
- The study highlights the non-unitary nature of certain DQCPs.
- Emergent symmetries in 1D DQCP models were detected.
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