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Nonperturbative renormalization group approach to the Ising model: a derivative expansion at order $\partial^4$

L. Canet·B. Delamotte·D. Mouhanna·J. Vidal
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Abstract

On the example of the three-dimensional Ising model, we show that nonperturbative renormalization group equations allow one to obtain very accurate critical exponents. Implementing the order $\partial^4$ of the derivative expansion leads to $ν=0.632$ and to an anomalous dimension $η=0.033$ which is significantly improved compared with lower orders calculations.

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L. Canet, B. Delamotte, D. Mouhanna, J. Vidal. 2003-09-22. Nonperturbative renormalization group approach to the Ising model: a derivative expansion at order $\partial^4$. https://doi.org/10.1103/physrevb.68.064421

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