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Novel order parameter to describe the critical behavior of Ising spin glass models

F. Roma·F. Nieto·A. J. Ramirez-Pastor·E. E. Vogel
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Abstract

A novel order parameter $Φ$ for spin glasses is defined based on topological criteria and with a clear physical interpretation. $Φ$ is first investigated for well known magnetic systems and then applied to the Edwards-Anderson $\pm J$ model on a square lattice, comparing its properties with the usual $q$ order parameter. Finite size scaling procedures are performed. Results and analyses based on $Φ$ confirm a zero temperature phase transition and allow to identify the low temperature phase. The advantages of $Φ$ are brought out and its physical meaning is established.

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F. Roma, F. Nieto, A. J. Ramirez-Pastor, E. E. Vogel. 2005-07-27. Novel order parameter to describe the critical behavior of Ising spin glass models. https://doi.org/10.1016/j.physa.2005.08.052

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