Defect fugacity, spin-wave stiffness and Tc of the 2d planar rotor model

Sengupta, S. ; Nielaba, P. ; Binder, K. (2000) Defect fugacity, spin-wave stiffness and Tc of the 2d planar rotor model EPL: Europhysics Letters, 50 (5). pp. 668-673. ISSN 0295-5075

[img]
Preview
PDF - Author Version
224kB

Official URL: http://iopscience.iop.org/0295-5075/50/5/668

Related URL: http://dx.doi.org/10.1209/epl/i2000-00322-3

Abstract

We obtain precise values for the fugacities of vortices in the 2d planar rotor model from Monte Carlo simulations in the sector with no vortices. The bare spin-wave stiffness is also calculated and shown to have significant anharmonicity. Using these as inputs in the KT recursion relations, we predict the temperature Tc=0.925, using linearised equations, and Tc=0.899 ± 0.005 using next higher-order corrections, at which vortex unbinding commences in the unconstrained system. The latter value, being in excellent agreement with all recent determinations of Tc, demonstrates that our method 1) constitutes a stringent measure of the relevance of higher-order terms in KT theory and 2) can be used to obtain transition temperatures in similar systems with modest computational effort.

Item Type:Article
Source:Copyright of this article belongs to EDP Sciences.
ID Code:56546
Deposited On:24 Aug 2011 11:07
Last Modified:18 May 2016 08:19

Repository Staff Only: item control page