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arXiv · 1609.02848

Critical behavior of dissipative two-dimensional spin lattices

R. Rota·F. Storme·N. Bartolo·R. Fazio·C. Ciuti
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Abstract

We explore critical properties of two-dimensional lattices of spins interacting via an anisotropic Heisenberg Hamiltonian and subject to incoherent spin flips. We determine the steady-state solution of the master equation for the density matrix via the corner-space renormalization method. We investigate the finite-size scaling and critical exponent of the magnetic linear susceptibility associated to a dissipative ferromagnetic transition. We show that the Von Neumann entropy increases across the critical point, revealing a strongly mixed character of the ferromagnetic phase. Entanglement is witnessed by the quantum Fisher information which exhibits a critical behavior at the transition point, showing that quantum correlations play a crucial role in the transition even though the system is in a mixed state.

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R. Rota, F. Storme, N. Bartolo, R. Fazio, C. Ciuti. 2016-09-09. Critical behavior of dissipative two-dimensional spin lattices. https://doi.org/10.1103/physrevb.95.134431

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