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arXiv · 1612.05466

Partition-free approach to open quantum systems in harmonic environments: an exact stochastic Liouville equation

G. M. G. McCaul·C. D. Lorenz·L. Kantorovich
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Abstract

We present a partition-free approach to the evolution of density matrices for open quantum systems coupled to a harmonic environment. The influence functional formalism combined with a two-time Hubbard-Stratonovich transformation allows us to derive a set of exact differential equations for the reduced density matrix of an open system, termed the Extended Stochastic Liouville-von Neumann equation. Our approach generalises previous work based on Caldeira-Leggett models and a partitioned initial density matrix. This provides a simple, yet exact, closed-form description for the evolution of open systems from equilibriated initial conditions. The applicability of this model and the potential for numerical implementations are also discussed.

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G. M. G. McCaul, C. D. Lorenz, L. Kantorovich. 2017-01-03. Partition-free approach to open quantum systems in harmonic environments: an exact stochastic Liouville equation. https://doi.org/10.1103/physrevb.95.125124

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