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Defect Energy with Conjugate Boundary Conditions in Spin Glass Models in Two Dimensions

Fumitaka Matsubara·Takayuki Shirakura·Michinori Siomi
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Abstract

We calculate the naive defect energy $ΔE$ of Ising spin glass(SG) models in two dimensions using conjugate boundary conditions. We predict that, in the $\pm J$ model, the averaged value $\bar{ΔE}$ converges to some non-zero value in the thermodynamic limit in contrast with $\bar{ΔE} = 0$ in the Gaussian model. This prediction is incompatible with previous ones but supports a recent Monte Carlo prediction of the presence of the SG phase at finite temperatures in the $\pm J$ Ising model. We also calculate the interface free energy to confirm it.

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Fumitaka Matsubara, Takayuki Shirakura, Michinori Siomi. 1998-06-29. Defect Energy with Conjugate Boundary Conditions in Spin Glass Models in Two Dimensions. https://doi.org/10.1103/physrevb.58.r11821

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