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arXiv · 1711.05162

Non-Markovianity in the optimal control of an open quantum system described by hierarchical equations of motion

Etienne Mangaud·Raijumon Puthumpally-Joseph·Dominique Sugny·Christoph Meier·Osman Atabek·Michèle Desouter-Lecomte
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Abstract

Optimal control theory is implemented with fully converged hierarchical equations of motion (HEOM) describing the time evolution of an open system density matrix strongly coupled to the bath in a spin-boson model. The populations of the two-level sub-system are taken as control objectives; namely, their revivals or exchange when switching off the field. We, in parallel, analyze how the optimal electric field consequently modifies the information back flow from the environment through different non-Markovian witnesses. Although the control field has a dipole interaction with the central sub-system only, its indirect influence on the bath collective mode dynamics is probed through HEOM auxiliary matrices, revealing a strong correlation between control and dissipation during a non-Markovian process. A heterojunction is taken as an illustrative example for modeling in a realistic way the two-level sub-system parameters and its spectral density function leading to a non-perturbative strong coupling regime with the bath. Although, due to strong system-bath couplings, control performances remain rather modest, the most important result is a noticeable increase of the non-Markovian bath response induced by the optimally driven processes.

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Etienne Mangaud, Raijumon Puthumpally-Joseph, Dominique Sugny, Christoph Meier, Osman Atabek, Michèle Desouter-Lecomte. 2017-11-14. Non-Markovianity in the optimal control of an open quantum system described by hierarchical equations of motion. https://doi.org/10.1088/1367-2630%2Faab651

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