1997/01/17 by Stefan Kehrein, Andreas Mielke
Physics and Astronomy · #Quantum Mechanics and Applications #Quantum chaos and dynamical systems #Quantum many-body systems #cond-mat.stat-mech
paper · pdf · doi:10.1023/a:1023289323069
4 pages, Latex, uses Revtex
arxiv created 1997/01/17 · openalex publication_date 1998/02/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
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.