Nonequilibrium dynamics in the Hubbard model
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Michael Moeckel
The (fermionic) Hubbard model is often considered as the paradigmatic
minimal model for correlated electrons on lattices. Recent progress in the
field of ultracold atom gases and pump-probe spectroscopy of correlated
materials has stimulated interest in its nonequilibrium properties. Those
can be probed by quantum quenches, i.e. nonadiabatic changes of parameters
(e.g. the interaction) in real time. I will briefly review my earlier work
based on perturbative and RG approaches to show that the response to small
quenches within the Fermi liquid regime is generic, i.e. does not depend on
the dimension (d>1) and lattice structure of the model [1]. Quenches across
the phase transition are numerically challenging. A brief outlook to recent
work [2] will be given which has shown that large similarities between the
real time and the imaginary time evolution exist which may allow to probe
dynamical critical exponents using imaginary time projector QMC methods with
i-time dependent Hamiltonians.
[1] M. Moeckel and S. Kehrein, PRL 100, 175702 (2008) [2] C. De Grandi,1 A.
Polkovnikov,2 and A. W. Sandvik arxiv 1301.2329 (2013)