https://doi.org/10.1140/epjd/e2004-00010-x
The non-Markovian quantum behavior of open systems
An exact Monte Carlo method employing stochastic product states
1
Physikalisches Institut, Universität Freiburg,
79104 Freiburg, Germany
2
Institut für Physik, Carl von Ossietzky
Universität, 26111 Oldenburg, Germany
Corresponding author: a breuer@physik.uni-freiburg.de
Received:
29
October
2003
Published online:
10
February
2004
It is shown that the exact dynamics of a composite quantum system can be represented through a pair of product states which evolve according to a Markovian random jump process. This representation is used to design a general Monte Carlo wave function method that enables the stochastic treatment of the full non-Markovian behavior of open quantum systems. Numerical simulations are carried out which demonstrate that the method is applicable to open systems strongly coupled to a bosonic reservoir, as well as to the interaction with a spin bath. Full details of the simulation algorithms are given, together with an investigation of the dynamics of fluctuations. Several potential generalizations of the method are outlined.
PACS: 03.65.Yz – Decoherence; open systems; quantum statistical methods / 02.70.Ss – Quantum Monte Carlo methods / 05.10.Gg – Stochastic analysis methods (Fokker-Planck, Langevin, etc.)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2004