Volume 81, Number 3, February 2008
Article Number 30008
Number of page(s) 6
Section General
Published online 03 January 2008
EPL, 81 (2008) 30008
DOI: 10.1209/0295-5075/81/30008

A study of logarithmic corrections and universal amplitude ratios in the two-dimensional 4-state Potts model

L. N. Shchur1, 2, B. Berche2 and P. Butera3

1  Landau Institute for Theoretical Physics, Russian Academy of Sciences - Chernogolovka 142432, Russia
2  Laboratoire de Physique des Matériaux, UMR CNRS 7556, Université Henri Poincaré, Nancy 1 B.P. 239, F-54506 Vandoeuvre les Nancy Cedex, France
3  Istituto Nazionale di Fisica Nucleare, Sezione di Milano-Bicocca - Piazza delle Scienze 3, 20126, Milano, Italia

received 16 July 2007; accepted in final form 4 December 2007; published February 2008
published online 3 January 2008

Monte Carlo (MC) and series expansion (SE) data for the energy, specific heat, magnetization and susceptibility of the two-dimensional 4-state Potts model in the vicinity of the critical point are analysed. The role of logarithmic corrections is discussed and an approach is proposed in order to account numerically for these corrections in the determination of critical amplitudes. Accurate estimates of universal amplitude ratios A+/A-, $\Gamma _{+}/\Gamma _{-}$, $\Gamma _{T}/\Gamma _{-}$ and $R_{C}^{\pm}$ are given, which arouse new questions with respect to previous works.

05.50.+q - Lattice theory and statistics (Ising, Potts, etc.).
75.10.-b - General theory and models of magnetic ordering.

© EPLA 2008