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Journal of Physics A Mathematical and General

Conformal invariance and non-universality in quantum spin chains with a defect

Luiz G. Guimarães, J. R. Drugowich de Felício

Published Apr 21, 1986• 20 citations
Publisher

Abstract

The authors study quantum analogues of two-dimensional Ising models with a linear defect. Conformal invariance and scaling arguments are used to relate the exponent eta * (of the time correlation function of the spin at the defect) to a finite chain mass-gap ratio. Close agreement is found with the pertinent exact results.
DOI
10.1088/0305-4470/19/6/008

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