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arXiv · 1303.5682

Charge and spin correlations of a Peierls insulator after a quench

Martin Hohenadler
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Abstract

Electron-phonon coupling plays a central role for time-dependent phenomena in condensed matter, for example in photo-excitation experiments. We use the continuous-time quantum Monte Carlo method to study the real-time evolution of charge and spin correlation functions of a Peierls insulator after a quench to a noninteracting Hamiltonian. This approach gives exact results, and fully takes into account quantum phonon effects without relying on a Hilbert space truncation. It is also free from a dynamical sign problem. The observed time dependence is compared to free-fermion time evolution starting from a dimerized state. Our exact results provide a benchmark for more realistic calculations, and may be directly applicable to experiments with cold atoms or trapped ions.

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Martin Hohenadler. 2013-03-22. Charge and spin correlations of a Peierls insulator after a quench. https://doi.org/10.1103/physrevb.88.064303

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