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arXiv · 0712.2009

Behavior of Ising Spin Glasses in a Magnetic Field

Thomas Jorg·Helmut G. Katzgraber·Florent Krzakala
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Abstract

We study the existence of a spin-glass phase in a field using Monte Carlo simulations performed along a nontrivial path in the field--temperature plane that must cross any putative de Almeida-Thouless instability line. The method is first tested on the Ising spin glass on a Bethe lattice where the instability line separating the spin glass from the paramagnetic state is also computed analytically. While the instability line is reproduced by our simulations on the mean-field Bethe lattice, no such instability line can be found numerically for the short-range three-dimensional model.

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Thomas Jorg, Helmut G. Katzgraber, Florent Krzakala. 2008-05-13. Behavior of Ising Spin Glasses in a Magnetic Field. https://doi.org/10.1103/physrevlett.100.197202

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