21 research outputs found
Non-Markovian decay and dynamics of decoherence in private and public environments
We study the decay process in an open system, emphasizing on the relevance of
the environment's spectral structure. Non-Markovian effects are included to
quantitatively analyze the degradation rate of the coherent evolution. The way
in which a two level system is coupled to different environments is
specifically addressed: multiple connections to a single bath (public
environment)or single connections to multiple baths (private environments). We
numerically evaluate the decay rate of a local excitation by using the Survival
Probability and the Loschmidt Echo. These rates are compared to analytical
results obtained from the standard Fermi Golden Rule (FGR) in Wide Band
Approximation, and a Self-Consistent evaluation that accounts for the bath's
memory in cases where an exact analytical solution is possible. We observe that
the correlations appearing in a public bath introduce further deviations from
the FGR as compared with a private bath.Comment: 18 pages, 7 figures. Accepted for publication in Physical Review