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Replica symmetry breaking solution for the fermionic Ising spin glass and the Ghatak-Sherrington model

H. Feldmann·R. Oppermann
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Abstract

We solve the fermionic version of the Ising spin glass for arbitrary filling μand temperature T taking into account replica symmetry breaking. Using a simple exact mapping from μto the anisotropy parameter D, we also obtain the solution of the S=1 Sherrington-Kirkpatrick model. An analytic expression for T=0 gives an improved critical value for the first-order phase transition. We revisit the question of stability against replica-diagonal fluctuations and find that the appearance of complex eigenvalues of the Almeida-Thouless matrix is not an artifact of the replica-symmetric approximation.

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H. Feldmann, R. Oppermann. 1999-10-04. Replica symmetry breaking solution for the fermionic Ising spin glass and the Ghatak-Sherrington model. https://doi.org/10.1088/0305-4470%2F33%2F7%2F303

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