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arXiv · 1306.5733

Non-equilibrium dynamics in the antiferromagnetic Hubbard model

Matteo Sandri·Michele Fabrizio
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Abstract

We investigate by means of the time-dependent Gutzwiller approximation the out-of-equilibrium dynamics of an antiferromagnetic state evolved with the Hubbard model Hamiltonian after a sudden change of the repulsion strength $U$. We find that magnetic order survives more than what expected on the basis of thermalization arguments, in agreement with recent DMFT calculations. In addition, we find evidence of a dynamical transition for quenches to large values of $U$ between a coherent antiferromagnet characterized by a finite quasiparticle residue to an incoherent one with vanishing residue, that finally turns into a paramagnet for even larger $U$.

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Matteo Sandri, Michele Fabrizio. 2013-06-24. Non-equilibrium dynamics in the antiferromagnetic Hubbard model. https://doi.org/10.1103/physrevb.88.165113

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