Combinatorial Approach to the Ground-State Energy of Square and Triangular +/- J Spin Glasses

P. Polaszek

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arXiv · cond-mat/9510116

Combinatorial Approach to the Ground-State Energy of Square and Triangular +/- J Spin Glasses

P. Polaszek

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Abstract

A new combinatorial, analytical approach to the ground-state energy problem of spin glasses with different concentrations of +/- J interactions is developed. The energy e_0 is expressed in terms of the fraction of broken bonds mu_0 and expanded into a fast converging series of the average length of a segment between two frustrated plaquettes of a minimum-weighted perfect matching Lambda_mean. The concept of so called diagram stability s is introduced in order to calculate coefficients of this expansion. Finally, the fraction mu_0 as a function of the concentration p of negative bonds is obtained for triangular and square infinite lattices in excellent accordance with numerical simulations of large adequate systems.

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P. Polaszek. 1995-10-20. Combinatorial Approach to the Ground-State Energy of Square and Triangular +/- J Spin Glasses. https://arxiv.org/abs/cond-mat/9510116

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