Berlin 2015 – wissenschaftliches Programm
TT 71.60: Poster
Mittwoch, 18. März 2015, 15:00–18:00, Poster B
Matrix-product-state method with local basis optimization for bosonic systems out of equilibrium — •Christoph Brockt1, Eric Jeckelmann1, Florian Dorfner2, Lev Vidmar2, and Fabian Heidrich-Meisner2 — 1Leibniz Universität Hannover, Germany — 2Ludwig-Maximilians-Universität München, Germany
We present a method for simulating the time evolution of quasi-one-dimensional correlated systems with bosonic degrees of freedom using matrix product states. Our goal is the accurate description of systems with large bosonic fluctuations for long periods of time. For this purpose we combine the time-evolving block decimation (TEBD) algorithm  with a local basis optimization approach which yields so-called optimal boson states . We discuss the performance of this approach in comparison to TEBD with a bare boson basis, exact diagonalizations, and diagonalizations in a limited functional space. First, we test our method for the non-equilibrium dynamics of a Holstein polaron  and show that it allows us to study the regime of strong electron-phonon coupling. Second, the method is applied to the scattering and self-trapping of an electronic gaussian wave packet traveling through a quantum wire with electron-phonon coupling. Support from the DFG through the Research Unit FOR 1807 is gratefully acknowledged.
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