Ground states and thermal states of the random field Ising model

Yong Wu; Jon Machta

doi:10.1103/physrevlett.95.137208

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arXiv · cond-mat/0501619

Ground states and thermal states of the random field Ising model

Yong Wu·Jon Machta

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Abstract

The random field Ising model is studied numerically at both zero and positive temperature. Ground states are mapped out in a region of random and external field strength. Thermal states and thermodynamic properties are obtained for all temperatures using the the Wang-Landau algorithm. The specific heat and susceptibility typically display sharp peaks in the critical region for large systems and strong disorder. These sharp peaks result from large domains flipping. For a given realization of disorder, ground states and thermal states near the critical line are found to be strongly correlated--a concrete manifestation of the zero temperature fixed point scenario.

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Yong Wu, Jon Machta. 2005-08-18. Ground states and thermal states of the random field Ising model. https://doi.org/10.1103/physrevlett.95.137208

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