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How to evaluate ground-state landscapes of disordered systems thermodynamical correctly

Alexander K. Hartmann
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Abstract

Ground states of three-dimensional EA Ising spin glasses are calculated for sizes up to 14^3 using a combination of a genetic algorithm and cluster-exact approximation. For each realization several independent ground states are obtained. Then, by applying ballistic search and T=0 Monte-Carlo simulations, it is ensured that each ground state appears with the same probability. Consequently, the results represent the true T=0 thermodynamic behavior. The distribution P(|q|) of overlaps is evaluated. For increasing size the width of P(|q|) and the fraction of the distribution below q_0=0.5 converge to zero. This indicates that for the infinite system P(|q|) is a delta function, in contrast to previous results. Thus, the ground-state behavior is dominated by few large clusters of similar ground states.

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Alexander K. Hartmann. 1999-06-17. How to evaluate ground-state landscapes of disordered systems thermodynamical correctly. https://doi.org/10.1007/s100510050066

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