Numerical Evidence for Multiplicative Logarithmic Corrections from Marginal Operators

Дата и время публикации : 1996-02-06T10:34:52Z

Авторы публикации и институты :
Sebastian Eggert (Chalmers TH, Gothenburg, Sweden)

Ссылка на журнал-издание: Phys.Rev. B54 (1996) 9612
Коментарии к cтатье: revised paper with extended data-analysis. 5 pages, using revtex with 4 embedded figures (included with macro). A complete postscript file with all figures + text (5 pages) is available from http://FY.CHALMERS.SE/~eggert/marginal.ps or by request from eggert@fy.chalmers.se
Первичная категория: cond-mat

Все категории : cond-mat, hep-th, nucl-th

Краткий обзор статьи: Field theory calculations predict multiplicative logarithmic corrections to correlation functions from marginally irrelevant operators. However, for the numerically most suitable model – the spin-1/2 chain – these corrections have been controversial. In this paper, the spin-spin correlation function of the antiferromagnetic spin-1/2 chain is calculated numerically in the presence of a next nearest neighbor coupling J2 for chains of up to 32 sites. By varying the coupling strength J2 we can control the effect of the marginal operator, and our results unambiguously confirm the field theory predictions. The critical value at which the marginal operator vanishes has been determined to be at J2 = 0.241167 +/- 0.000005J.

Category: Physics