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Updated: May 25, 2026

Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Boson pairing and unusual criticality in a generalized XY model
Yifei Shi1, Austen Lamacraft, Paul Fendley
1Department of Physics, University of Virginia, Charlottesville, Virginia 22904-4714, USA.
Abstract:
We discuss the unusual critical behavior of a generalized XY model containing both 2π-periodic and π-periodic couplings between sites, allowing for ordinary vortices and half-vortices. The phase diagram of this system includes both single-particle condensate and pair-condensate phases. Using a field theoretic formulation and worm algorithm Monte Carlo simulations, we show that in two dimensions it is possible for the system to pass directly from the disordered (high temperature) phase to the single particle (quasi)condensate via an Ising transition, a situation reminiscent of the "deconfined criticality" scenario.
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