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Correlated correlation functions in random-bond ferromagnets

Tom Davis·John Cardy
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Abstract

The two-dimensional random-bond Q-state Potts model is studied for Q near 2 via the perturbative renormalisation group to one loop. It is shown that weak disorder induces cross-correlations between the quenched-averages of moments of the two-point spin/spin and energy/energy correlation functions, which should be observable numerically in specific linear combinations of various quenched correlation functions. The random-bond Ising model in (2+epsilon) dimensions is similarly treated. As a byproduct, a simple method for deriving the scaling dimensions of all moments of the local energy operator is presented.

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Tom Davis, John Cardy. 1999-11-05. Correlated correlation functions in random-bond ferromagnets. https://doi.org/10.1016/s0550-3213(99)00786-5

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