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Driven Random Field Ising Model: some exactly solved examples in threshold activated kinetics

Prabodh Shukla
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Abstract

The random field Ising model driven by a slowly varying uniform external field at zero temperature provides a caricature of several threshold activated systems. In this model, the non-equilibrium response of the system can be obtained analytically on a Bethe lattice if the initial state of the system has all spins aligned parallel to each other. We consider ferromagnetic as well as anti-ferromagnetic interactions. The ferromagnetic model exhibits avalanches and non-equilibrium critical behavior. The anti-ferromagnetic model is marked by the absence of these features. The ferromagnetic model is Abelian, and the anti-ferromagnetic model is non-Abelian. Theoretical approaches based on the probabilistic method are discussed in the two cases, and illustrated by deriving some basic results.

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BibTeXRIS

Prabodh Shukla. 2004-01-15. Driven Random Field Ising Model: some exactly solved examples in threshold activated kinetics. https://doi.org/10.1142/s0217979203023276

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