Dynamics of a Large-Spin System in the Strong Coupling Regime
Abstract
We investigate collective effects of an ensemble of biased two-level systems interacting with a bosonic bath in the strong coupling regime. The two level systems are described by a large pseudo-spin J. An equation for the expectation value M(t) of the z-component of the pseudo spin is derived and solved numerically for an ohmic bath at T = 0. In case of a large cut-off frequency of the spectral function, a Markov approximation is justified and an analytical solution is presented. We find that M(t) relaxes towards a highly correlated state with maximum value ±J for large times. However, this relaxation is extremely slow for most parameter values so as if the system was "frozen in" by interaction with the bosonic bath.
- Publication:
-
Recent Progress in Many-Body Theories
- Pub Date:
- December 2002
- DOI:
- 10.1142/9789812777843_0058
- arXiv:
- arXiv:cond-mat/0111220
- Bibcode:
- 2002rpmb.conf..487V
- Keywords:
-
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 4 pages, 2 figures, to be published in proceedings of MB11