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One-step replica symmetry breaking solution for fermionic Ising spin glass in a transverse field

F. M. Zimmer·S. G. Magalhaes
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Abstract

The fermionic Ising spin glass models in a transverse field are investigated in a Grassmann path integral formalism. The Parisi's scheme of one-step replica symmetry breaking (RSB) is used within the static ansatz. This formalism has already been applied in a theory in which $m$ (Parisi's block-size parameter) is taken as a constant (PRB 72, 014447 (2005)). Now, it is extended to consider $m$ as a variational parameter. In this case, the results show that RSB is present when $T\to0$, in which the system is driven by quantum fluctuations.

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F. M. Zimmer, S. G. Magalhaes. 2006-06-09. One-step replica symmetry breaking solution for fermionic Ising spin glass in a transverse field. https://doi.org/10.1103/physrevb.74.012202

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