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arXiv · 1301.2453

Adaptive Resummation of Markovian Quantum Dynamics

Felix Lucas·Klaus Hornberger
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Abstract

We introduce a method for obtaining analytic approximations to the evolution of Markovian open quantum systems. It is based on resumming a generalized Dyson series in a way that ensures optimal convergence even in the absence of a small parameter. The power of this approach is demonstrated by two benchmark examples: the spatial detection of a free particle and the Landau-Zener problem in the presence of dephasing. The derived approximations are asymptotically exact and exhibit errors on the per mil level over the entire parameter range.

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Felix Lucas, Klaus Hornberger. 2013-01-11. Adaptive Resummation of Markovian Quantum Dynamics. https://doi.org/10.1103/physrevlett.110.240401

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