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Spin-boson dynamics: A unified approach from weak to strong coupling

Francesco Nesi·Elisabetta Paladino·Michael Thorwart·Milena Grifoni
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Abstract

We present a novel approximation scheme to describe the influence of a harmonic bath on the dynamics of a two-level particle over almost the whole regime of temperatures and coupling to the environment, for a wide class of bath spectral densities. Starting from the exact path-integral solution for the two-level system density matrix, effective intra-blip correlations are fully included, while inter-blip and blip-sojourn interactions are considered up to first order. In the proper regimes, an excellent agreement with conventional perturbative approaches and ab-initio path-integral results is found.

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Francesco Nesi, Elisabetta Paladino, Michael Thorwart, Milena Grifoni. 2007-06-27. Spin-boson dynamics: A unified approach from weak to strong coupling. https://doi.org/10.1209/0295-5075%2F80%2F40005

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