Phase Transitions In Two Planar Lattice Models And Topological Defects: A Monte Carlo Study

TL;DR

This study uses Monte Carlo simulations to explore how suppressing topological defects affects phase transitions in two planar lattice models, revealing that defect suppression can eliminate or alter the nature of these transitions.

Contribution

It demonstrates how topological defect suppression influences phase transition types and temperatures in P(2) and P(4) models, providing new insights into defect-related phase behavior.

Findings

Suppression of 1/2-defects eliminates phase transition in P(2) model.

In P(4) model, suppressing single 1/2-defects changes first order to second order transition.

Complete defect suppression removes phase transition entirely.

Abstract

Monte Carlo simulation has been performed in the planar P(_{2}) and P(_{4}) models to investigate the effects of the suppression of topological defects on the phase transition exhibited by these models. Suppression of the 1/2-defects on the square plaquettes in the P(_{2}) model leads to complete elimination of the phase transition observed in this model. However in the P(_{4}) model, on suppressing the single 1/2-defects on square plaquettes, the otherwise first order phase transition changes to a second order one which occurs at a higher temperature and this is due to presence of large number of 1/2-pair defects which are left within the square plaquettes. When we suppressed these charges too, complete elimination of phase transition was observed.