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arXiv · 2611.08564

Thermodynamics of Speed and Efficiency with Quantum Feedback

Yue Liu·Ryotaro Honma·Ruicheng Bao·Tan Van Vu
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Abstract

Rapid thermodynamic operations generally entail irreversible dissipation, giving rise to trade-offs between operating speed and thermodynamic cost. Yet, how quantum feedback fundamentally reshapes these trade-offs remains elusive. Here, we derive a finite-time current--dissipation relation for continuously monitored open quantum dynamics with jump feedback. From this fundamental relation, we establish a quantum speed limit and a power-efficiency trade-off for stationary information engines, identifying how feedback affects state transformations and the performance of engines through both informational entropy and direct dynamical contributions. Our results provide a quantitative foundation for fast, low-dissipation quantum thermodynamics in the presence of feedback control, exemplified by attaining the generalized Landauer bound in finite-time information erasure and approaching unit information efficiency at finite power in the large-system limit of a collective engine.

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Yue Liu, Ryotaro Honma, Ruicheng Bao, Tan Van Vu. 2026-11-05. Thermodynamics of Speed and Efficiency with Quantum Feedback. https://arxiv.org/abs/2611.08564

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