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arXiv · 0706.2866

Matching Kasteleyn Cities for Spin Glass Ground States

Creighton K. Thomas·A. Alan Middleton
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Abstract

As spin glass materials have extremely slow dynamics, devious numerical methods are needed to study low-temperature states. A simple and fast optimization version of the classical Kasteleyn treatment of the Ising model is described and applied to two-dimensional Ising spin glasses. The algorithm combines the Pfaffian and matching approaches to directly strip droplet excitations from an excited state. Extended ground states in Ising spin glasses on a torus, which are optimized over all boundary conditions, are used to compute precise values for ground state energy densities.

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Creighton K. Thomas, A. Alan Middleton. 2007-11-20. Matching Kasteleyn Cities for Spin Glass Ground States. https://doi.org/10.1103/physrevb.76.220406

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