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Equilibrium Correlation Functions of the Spin-Boson Model with Sub-Ohmic Bath

T. Stauber·A. Mielke
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Abstract

The spin-boson model is studied by means of flow equations for Hamiltonians. Our truncation scheme includes all coupling terms which are linear in the bosonic operators. Starting with the canonical generator $η_c=[H_0,H]$ with $H_0$ resembling the non-interacting bosonic bath, the flow equations exhibit a universal attractor for the Hamiltonian flow. This allows to calculate equilibrium correlation functions for super-Ohmic, Ohmic and sub-Ohmic baths within a uniform framework including finite bias.

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T. Stauber, A. Mielke. 2002-09-30. Equilibrium Correlation Functions of the Spin-Boson Model with Sub-Ohmic Bath. https://doi.org/10.1016/s0375-9601(02)01416-0

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