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Replica field theory and renormalization group for the Ising spin glass in an external magnetic field

T. Temesvari·C. De Dominicis
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Abstract

We use the generic replica symmetric cubic field-theory to study the transition of short range Ising spin glasses in a magnetic field around the upper critical dimension, d=6. A novel fixed-point is found, in addition to the well-known zero magnetic field fixed-point, from the application of the renormalization group. In the spin glass limit, n going to 0, this fixed-point governs the critical behaviour of a class of systems characterised by a single cubic interaction parameter. For this universality class, the spin glass susceptibility diverges at criticality, whereas the longitudinal mode remains massive. The third mode, the so-called anomalous one, however, behaves unusually, having a jump at criticality. The physical consequences of this unusual behaviour are discussed, and a comparison with the conventional de Almeida-Thouless scenario presented.

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T. Temesvari, C. De Dominicis. 2002-07-22. Replica field theory and renormalization group for the Ising spin glass in an external magnetic field. https://doi.org/10.1103/physrevlett.89.097204

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