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Title: 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.  more » « less
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SciPost Physics
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National Science Foundation
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