Logarithmic corrections to correlation decay in two-dimensional random-bond Ising systems

Abstract

The statistics of critical spin-spin correlation functions in Ising systems with non-frustrated disorder are investigated on a strip geometry, via numerical transfer-matrix techniques. Conformal invariance concepts are used, in order to test for logarithmic corrections to pure power-law decay against distance. Fits of our data to conformal-invariance expressions, specific to logarithmic corrections to correlations on strips, give results with the correct sign, for the moments of order $n=0-4$ of the correlation-function distribution. We find an interval of disorder strength along which corrections to pure-system behavior can be decomposed into the product of a known $n$-dependent factor and an approximately $n$-independent one, in accordance with predictions. A phenomenological fitting procedure is proposed, which takes partial account of subdominant terms of correlation-function decay on strips. In the low-disorder limit, it gives results in fairly good agreement with theoretical predictions, provided that an additional assumption is made.

arXiv commentFinal version, accepted for publication in Physical Review E

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Cited by in corpus (5)

• Self-Consistent Scaling Theory for Logarithmic Correction Exponents
• Universal dependence on disorder of 2D randomly diluted and random-bond +-J Ising models
• Scaling Analysis of the Site-Diluted Ising Model in Two Dimensions
• Quenched bond randomness in marginal and non-marginal Ising spin models in 2D
• Critical behavior of the pure and random-bond two-dimensional triangular Ising ferromagnet