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Abstract We develop a nonequilibrium increment method in quantum Monte Carlo simulations to obtain the Rényi entanglement entropy of various quantum many-body systems with high efficiency and precision. To demonstrate its power, we show the results on a few important yet difficult (2 + 1) d quantum lattice models, ranging from the Heisenberg quantum antiferromagnet with spontaneous symmetry breaking, the quantum critical point with O(3) conformal field theory (CFT) to the toric code $${{\mathbb{Z}}}_{2}$$ Z 2 topological ordered state and the Kagome $${{\mathbb{Z}}}_{2}$$ Z 2 quantum spin liquid model with frustration and multi-spin interactions. In all these cases, our method either reveals the precise CFT data from the logarithmic correction or extracts the quantum dimension in topological order, from the dominant area law in finite-size scaling, with very large system sizes, controlled errorbars, and minimal computational costs. Our method, therefore, establishes a controlled and practical computation paradigm to obtain the difficult yet important universal properties in highly entangled quantum matter.
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Scaling of the disorder operator at deconfined quantum criticality
We study scaling behavior of the disorder parameter, defined as theexpectation value of a symmetry transformation applied to a finiteregion, at the deconfined quantum critical point in (2+1)d in the J-Q_3 J − Q 3 model via large-scale quantum Monte Carlo simulations. We show that thedisorder parameter for U(1) spin rotation symmetry exhibits perimeterscaling with a logarithmic correction associated with sharp corners ofthe region, as generally expected for a conformally-invariant criticalpoint. However, for large rotation angle the universal coefficient ofthe logarithmic corner correction becomes negative, which is not allowedin any unitary conformal field theory. We also extract the currentcentral charge from the small rotation angle scaling, whose value ismuch smaller than that of the free theory.
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- Award ID(s):
- 1846109
- PAR ID:
- 10400893
- Date Published:
- Journal Name:
- SciPost Physics
- Volume:
- 13
- Issue:
- 6
- ISSN:
- 2542-4653
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.21468/SciPostPhys.13.6.123
