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arXiv · 2501.04895

Response kinetic uncertainty relation for Markovian open quantum systems

Kangqiao Liu·Jie Gu
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Abstract

Response uncertainty relations in stochastic thermodynamics extend precision bounds to the sensitivity of observables under external perturbations. Here we derive a quantum response kinetic uncertainty relation for continuously monitored Markovian open quantum systems in the steady state of the Lindblad master equation. The response precision of a measured trajectory observable is bounded by two contributions: the conventional quantum dynamical activity and a perturbation-induced intersubspace transition term. The latter is absent in the classical limit and captures a genuinely quantum part of the response cost. We identify simple conditions under which either contribution vanishes, and we further clarify the structure of the intersubspace term through a symmetry-resolved decomposition and exact sector-selection rules. The bound and its structure are illustrated in a driven two-level atom.

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Kangqiao Liu, Jie Gu. 2025-01-09. Response kinetic uncertainty relation for Markovian open quantum systems. https://doi.org/10.1103/ps1b-8l1x

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