Critical Behavior of Random Bond Potts Models

Дата и время публикации : 1997-05-05T23:48:35Z

Авторы публикации и институты :
John Cardy
Jesper Lykke Jacobsen

Ссылка на журнал-издание: Phys. Rev. Lett. 79, 4063 (1997).
Коментарии к cтатье: 13 pages, RevTeX. 4 figures included. Submitted to Phys.Rev.Lett
Первичная категория: cond-mat.stat-mech

Все категории : cond-mat.stat-mech

Краткий обзор статьи: The effect of quenched impurities on systems which undergo first-order phase transitions is studied within the framework of the q-state Potts model. For large q a mapping to the random field Ising model is introduced which provides a simple physical explanation of the absence of any latent heat in 2D, and suggests that in higher dimensions such systems should exhibit a tricritical point with a correlation length exponent related to the exponents of the random field model by nu = nu_RF / (2 – alpha_RF – beta_RF). In 2D we analyze the model using finite-size scaling and conformal invariance, and find a continuous transition with a magnetic exponent beta / nu which varies continuously with q, and a weakly varying correlation length exponent nu approx 1. We find strong evidence for the multiscaling of the correlation functions as expected for such random systems.

Category: Physics