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arXiv · 2404.01285

Weak-coupling limits of the quantum Langevin equation for an oscillator

Aritra Ghosh·Sushanta Dattagupta
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Abstract

The quantum Langevin equation as obtained from the independent-oscillator model describes a strong-coupling situation, devoid of the Born-Markov approximation that is employed in the context of the Gorini-Kossakowski-Sudarshan-Lindblad equation. The question we address is what happens when we implement such 'Born-Markov'-like approximations at the level of the quantum Langevin equation for a harmonic oscillator which carries a noise term satisfying a fluctuation-dissipation theorem. In this backdrop, we also comment on the rotating-wave approximation.

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Aritra Ghosh, Sushanta Dattagupta. 2024-04-01. Weak-coupling limits of the quantum Langevin equation for an oscillator. https://doi.org/10.1016/j.physa.2024.129926

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