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arXiv · 1010.2853

Optimal ramp shapes for the fermionic Hubbard model in infinite dimensions

Nikolai Eurich·Martin Eckstein·Philipp Werner
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Abstract

We use non-equilibrium dynamical mean field theory and a real-time diagrammatic impurity solver to study the heating associated with time-dependent changes of the interaction in a fermionic Hubbard model. Optimal ramp shapes U(t) which minimize the excitation energy are determined for an infinitesimal change. For ramp times of a few inverse hoppings, these optimal U(t) are strongly oscillating with a frequency determined by the bandwidth. We show that the scaled versions of the optimized ramps yield substantially lower temperatures than linear ramps even far outside the perturbative regime.

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Nikolai Eurich, Martin Eckstein, Philipp Werner. 2011-05-02. Optimal ramp shapes for the fermionic Hubbard model in infinite dimensions. https://doi.org/10.1103/physrevb.83.155122

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