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arXiv · 2103.07255

Determination of the critical exponents in dissipative phase transitions: Coherent anomaly approach

Jiasen Jin·Wen-Bin He·Fernando Iemini·Diego Ferreira·Ying-Dan Wang·Stefano Chesi·Rosario Fazio
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Abstract

We propose a generalization of the coherent anomaly method to extract the critical exponents of a phase transition occurring in the steady-state of an open quantum many-body system. The method, originally developed by Suzuki [J. Phys. Soc. Jpn. {\bf 55}, 4205 (1986)] for equilibrium systems, is based on the scaling properties of the singularity in the response functions determined through cluster mean-field calculations. We apply this method to the dissipative transverse-field Ising model and the dissipative XYZ model in two dimensions obtaining convergent results already with small clusters.

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Jiasen Jin, Wen-Bin He, Fernando Iemini, Diego Ferreira, Ying-Dan Wang, Stefano Chesi, Rosario Fazio. 2021-03-12. Determination of the critical exponents in dissipative phase transitions: Coherent anomaly approach. https://doi.org/10.1103/physrevb.104.214301

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