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arXiv · 1303.4618

Nonequilibrium dynamical mean field simulation of inhomogeneous systems

Martin Eckstein·Philipp Werner
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Abstract

We extend the nonequilibrium dynamical mean field (DMFT) formalism to inhomogeneous systems by adapting the "real-space" DMFT method to Keldysh Green's functions. Solving the coupled impurity problems using strong-coupling perturbation theory, we apply the formalism to homogeneous and inhomogeneous layered systems with strong local interactions and up to 39 layers. We study the diffusion of doublons and holes created by photo-excitation in a Mott insulating system, the time-dependent build-up of the polarization and the current induced by a linear voltage bias across a multi-layer structure, and the photo-induced current in a Mott insulator under bias.

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Martin Eckstein, Philipp Werner. 2013-03-19. Nonequilibrium dynamical mean field simulation of inhomogeneous systems. https://doi.org/10.1103/physrevb.88.075135

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