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Reduction of Two-Dimensional Dilute Ising Spin Glasses

S. Boettcher·A. K. Hartmann
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Abstract

The recently proposed reduction method is applied to the Edwards-Anderson model on bond-diluted square lattices. This allows, in combination with a graph-theoretical matching algorithm, to calculate numerically exact ground states of large systems. Low-temperature domain-wall excitations are studied to determine the stiffness exponent y_2. A value of y_2=-0.281(3) is found, consistent with previous results obtained on undiluted lattices. This comparison demonstrates the validity of the reduction method for bond-diluted spin systems and provides strong support for similar studies proclaiming accurate results for stiffness exponents in dimensions d=3,...,7.

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S. Boettcher, A. K. Hartmann. 2005-03-18. Reduction of Two-Dimensional Dilute Ising Spin Glasses. https://doi.org/10.1103/physrevb.72.014429

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