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arXiv · 1708.08666

Linked cluster expansions for open quantum systems on a lattice

Abstract

We propose a generalization of the linked-cluster expansions to study driven-dissipative quantum lattice models, directly accessing the thermodynamic limit of the system. Our method leads to the evaluation of the desired extensive property onto small connected clusters of a given size and topology. We first test this approach on the isotropic spin-1/2 Hamiltonian in two dimensions, where each spin is coupled to an independent environment that induces incoherent spin flips. Then we apply it to the study of an anisotropic model displaying a dissipative phase transition from a magnetically ordered to a disordered phase. By means of a Padé analysis on the series expansions for the average magnetization, we provide a viable route to locate the phase transition and to extrapolate the critical exponent for the magnetic susceptibility.

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Alberto Biella, Jiasen Jin, Oscar Viyuela, Cristiano Ciuti, Rosario Fazio, Davide Rossini. 2017-11-12. Linked cluster expansions for open quantum systems on a lattice. https://doi.org/10.1103/physrevb.97.035103

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