Flow equation renormalization of a spin-boson model with a structured bath

Silvia Kleff; Stefan Kehrein; Jan von Delft

doi:10.1016/s1386-9477(02)01083-4

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Flow equation renormalization of a spin-boson model with a structured bath

Silvia Kleff·Stefan Kehrein·Jan von Delft

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Abstract

We discuss the dynamics of a spin coupled to a damped harmonic oscillator. This system can be mapped to a spin-boson model with a structured bath, i.e. the spectral function of the bath has a resonance peak. We diagonalize the model by means of infinitesimal unitary transformations (flow equations), thereby decoupling the small quantum system from its environment, and calculate spin-spin correlation functions.

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Silvia Kleff, Stefan Kehrein, Jan von Delft. 2003-02-18. Flow equation renormalization of a spin-boson model with a structured bath. https://doi.org/10.1016/s1386-9477(02)01083-4

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