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arXiv · 2303.09584

Time-dependent ghost-Gutzwiller non-equilibrium dynamics

Daniele Guerci·Massimo Capone·Nicola Lanatà
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Abstract

We introduce the time-dependent ghost Gutzwiller approximation (td-gGA), a non-equilibrium extension of the ghost Gutzwiller approximation (gGA), a powerful variational approach which systematically improves on the standard Gutzwiller method by including auxiliary degrees of freedom. We demonstrate the effectiveness of td-gGA by studying the quench dynamics of the single-band Hubbard model as a function of the number of auxiliary parameters. Our results show that td-gGA captures the relaxation of local observables, in contrast with the time-dependent Gutzwiller method. This systematic and qualitative improvement leads to an accuracy comparable with time-dependent Dynamical Mean-Field Theory which comes at a much lower computational cost. These findings suggest that td-gGA has the potential to enable extensive and accurate theoretical investigations of multi-orbital correlated electron systems in nonequilibrium situations, with potential applications in the field of quantum control, Mott solar cells, and other areas where an accurate account of the non-equilibrium properties of strongly interacting quantum systems is required.

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Daniele Guerci, Massimo Capone, Nicola Lanatà. 2023-03-16. Time-dependent ghost-Gutzwiller non-equilibrium dynamics. https://doi.org/10.1103/physrevresearch.5.l032023

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