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arXiv · 2507.11712

Separation of relaxation timescales via strong system-bath coupling: Dissipative three-level system as a case study

Brett Min·Matthew Gerry·Dvira Segal
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Abstract

We analytically demonstrate that strong system-bath coupling separates the relaxation dynamics of a dissipative quantum system into two distinct regimes: a short-time dynamics that, as expected, accelerates with increasing coupling to the environment, and a slow dynamics that, counterintuitively, becomes increasingly prolonged at sufficiently strong coupling. Using the reaction-coordinate polaron-transform mapping, we uncover the general mechanism behind this effect and derive accurate expressions for both relaxation timescales. Numerical simulations confirm our analytical predictions. From a practical perspective, our results suggest that strong coupling to a dissipative bath can autonomously generate and sustain long-lived quantum coherences, offering a promising strategy for bath-engineered quantum state preparation.

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Brett Min, Matthew Gerry, Dvira Segal. 2025-07-15. Separation of relaxation timescales via strong system-bath coupling: Dissipative three-level system as a case study. https://doi.org/10.1103/31cp-kq8f

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