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arXiv · 1903.03861

Correlation Picture Approach to Open-Quantum-System Dynamics

S. Alipour·A. T. Rezakhani·A. P. Babu·K. Mølmer·M. Möttönen·T. Ala-Nissila
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Abstract

We introduce a new dynamical picture, referred to as correlation picture,' which connects a correlated state to its uncorrelated counterpart. Using this picture allows us to derive an exact dynamical equation for a general open-system dynamics with system--environment correlations included. This exact dynamics is in the form of a Lindblad-like equation even in the presence of initial system-environment correlations. For explicit calculations, we also develop a weak-correlation expansion formalism that allows us to perform systematic perturbative approximations. This expansion provides approximate master equations which can feature advantages over existing weak-coupling techniques. As a special case, we derive a Markovian master equation, which is different from existing approaches. We compare our equations with corresponding standard weak-coupling equations by two examples, where our correlation picture formalism is more accurate, or at least as accurate as weak-coupling equations.

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S. Alipour, A. T. Rezakhani, A. P. Babu, K. Mølmer, M. Möttönen, T. Ala-Nissila. 2020-05-13. Correlation Picture Approach to Open-Quantum-System Dynamics. https://doi.org/10.1103/physrevx.10.041024

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