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arXiv · 1510.05866

Nonequilibrium variational-cluster approach to real-time dynamics in the Fermi-Hubbard model

Felix Hofmann·Martin Eckstein·Michael Potthoff
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Abstract

The nonequilibrium variational-cluster approach is applied to study the real-time dynamics of the double occupancy in the one-dimensional Fermi-Hubbard model after different fast changes of hopping parameters. A simple reference system, consisting of isolated Hubbard dimers, is used to discuss different aspects of the numerical implementation of the approach in the general framework of nonequilibrium self-energy functional theory. Opposed to a direct solution of the Euler equation, its time derivative is found to serve as numerically tractable and stable conditional equation to fix the time-dependent variational parameters.

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Felix Hofmann, Martin Eckstein, Michael Potthoff. 2016-04-14. Nonequilibrium variational-cluster approach to real-time dynamics in the Fermi-Hubbard model. https://doi.org/10.1088/1742-6596%2F696%2F1%2F012002

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