Abstract
Memory effects in quantum dynamical processes involving structured environments are presently difficult, if not impossible, to investigate using standard approaches. Progress can be made by transforming the environmental variables to a suitable chain representation which effectively performs a Markovian embedding of the dynamics. Here, we show that this effective-mode chain representation provides a unique way of unraveling the memory kernel as a function of time. Truncated or Markov-closed chains with effective modes exactly reproduce to the th order in time, up to an irrelevant constant of order . These favorable convergence properties pave the way for efficient quantum simulations of fast (non-Markovian) processes by reduced dynamical models.
- Received 20 April 2011
DOI:https://doi.org/10.1103/PhysRevE.84.030102
©2011 American Physical Society