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Published on: November 15, 2013
New ordered phases in a class of generalized XY models
Fábio C Poderoso1, Jeferson J Arenzon, Yan Levin
1Instituto de Física, Universidade Federal do Rio Grande do Sul, CP 15051, 91501-970 Porto Alegre, RS, Brazil.
Physical Review Letters
|March 17, 2011
Summary
The 2D XY model with nematic coupling shows new ordered phases and transitions. These transitions, driven by harmonic competition, belong to the Potts, Ising, or Kosterlitz-Thouless universality classes.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
Background:
- The 2D XY model is known for its Kosterlitz-Thouless (KT) phase transition.
- Adding nematic coupling introduces an Ising universality class phase transition.
Purpose of the Study:
- Investigate the impact of higher order harmonics on the 2D XY model with nematic coupling.
- Characterize the resulting phase diagram and new phase transitions.
Main Methods:
- Extensive Monte Carlo simulations
- Finite size scaling analysis
Main Results:
- Higher order harmonics qualitatively alter the phase diagram.
- New ordered phases emerge due to competition between ferromagnetic and pseudonematic couplings.
- Identified new phase transitions belonging to 2D Potts, Ising, or KT universality classes.
Conclusions:
- The interplay of couplings and harmonics creates a complex phase diagram.
- The study reveals novel phase transitions in the 2D XY model.
- Understanding these transitions is crucial for condensed matter systems.
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