Journal of Physical Studies
A three-dimensional random Ising model: Resummation of five-loop series
Viktoria Blavatska, Yurij V. Holovatch
Abstract
We investigate the critical behaviour of a d = 3-dimensional weakly diluted quenched Ising model, analyzing the series for the renormalization group functions at d = 3 obtained in a minimal subtraction scheme.Formerly it was established [R.Folk, Yu.Holovatch, T. Yavorskii, Phys.Rev. B 61, 15 114 (2000)℄ that the resummed renormalization group series possess an \optimal truncation" behaviour, provided that a Chisholm{Borel resummation technique is applied.This resulted in a conjecture that a four-loop approximation is a nal one for the random Ising model renormalizationgroup functions in a d = 3 minimal subtraction scheme.We apply the method of subsequent resummation, developed in the context of the d = 0-dimensional random Ising model, discuss the convergence properties of the series and give the results of the critical exponents increasing the order of approximation to 5-loop level.