Uniformly frustrated XY model without vortex-pattern ordering

S. E. Korshunov

doi:10.1103/physrevlett.94.087001

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arXiv · cond-mat/0409575

Uniformly frustrated XY model without vortex-pattern ordering

S. E. Korshunov

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Abstract

The uniformly frustrated XY model with f=1/3 on a dice lattice is shown to possess a so well developed accidental degeneracy of its ground states that the difference between the free energies of fluctuations does not lead to the stabilization of a particular vortex pattern down to zero temperature. Nonetheless, at low temperatures the system is characterized by a finite helicity modulus whose vanishing (at a finite temperature) is related with the dissociation of half-vortex pairs.

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S. E. Korshunov. 2004-09-22. Uniformly frustrated XY model without vortex-pattern ordering. https://doi.org/10.1103/physrevlett.94.087001

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