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Diagonalization of system plus environment Hamiltonians

Stefan Kehrein·Andreas Mielke
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Abstract

A new approach to dissipative quantum systems modelled by a system plus environment Hamiltonian is presented. Using a continuous sequence of infinitesimal unitary transformations the small quantum system is decoupled from its thermodynamically large environment. Dissipation enters through the observation that system observables generically decay completely into a different structure when the Hamiltonian is transformed into diagonal form. The method is particularly suited for studying low-temperature properties. This is demonstrated explicitly for the super-Ohmic spin-boson model.

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Stefan Kehrein, Andreas Mielke. 1997-01-17. Diagonalization of system plus environment Hamiltonians. https://doi.org/10.1023/a%3A1023289323069

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