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Ground state non-universality in the random field Ising model

P. M. Duxbury·J. H. Meinke
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Abstract

Two attractive and often used ideas, namely universality and the concept of a zero temperature fixed point, are violated in the infinite-range random-field Ising model. In the ground state we show that the exponents can depend continuously on the disorder and so are non-universal. However, we also show that at finite temperature the thermal order parameter exponent one half is restored so that temperature is a relevant variable. The broader implications of these results are discussed.

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P. M. Duxbury, J. H. Meinke. 2001-01-16. Ground state non-universality in the random field Ising model. https://doi.org/10.1103/physreve.64.036112

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