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Quantum Critical Point of the XY Model and Condensation of Field-Induced Quasiparticles in Dimer Compounds

Naoki Kawashima
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Abstract

The quantum critical point of the three-dimensional XY model in a symmetry-preserving field is investigated. The results of Monte Carlo simulations with the directed-loop algorithm show that the quantum critical behavior is characterized by the mean-field values of critical exponents. The system-size dependence of various quantities is compared to a simple field-theoretical argument that supports the mean-field scaling.

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Naoki Kawashima. 2004-10-05. Quantum Critical Point of the XY Model and Condensation of Field-Induced Quasiparticles in Dimer Compounds. https://doi.org/10.1143/jpsj.73.3219

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