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The Ising spin glass in a transverse field. Results of two fermionic models

A Theumann·A A Schmidt·S G Magalhaes
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Abstract

We analyze the long range Ising spin glass in a transverse field by using Grassmann variables in a field theory where the spin operators are represented by bilinear combinations of fermionic fields. We compare the results of two fermionic models. In the four state (4S)-model the diagonal Sz operator has two vanishing eigenvalues, that are suppressed by a restraint in the two states (2S)-model. Within a replica symmetric theory and in the static approximation we obtain similar results for both models.

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A Theumann, A A Schmidt, S G Magalhaes. 2001-09-06. The Ising spin glass in a transverse field. Results of two fermionic models. https://doi.org/10.1016/s0378-4371(02)00810-5

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