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arXiv · 2301.00566

Quantum speed limit for complex dynamics

Mao Zhang·Huai-Ming Yu·Jing Liu
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Abstract

Quantum speed limit focuses on the minimum time scale for a fixed mission and hence is important in quantum information where fast dynamics is usually beneficial. Most existing tools for the depiction of quantum speed limit are the lower-bound-type tools, which are in fact difficult to reveal the true minimum time, especially for many-body systems or complex dynamics. Therefore, the evaluation of this true minimum time in these scenarios is still an unsolved problem. Hereby we propose a three-step (classification-regression-calibration) methodology based on machine learning to evaluate the true minimum time in complex dynamics. Moreover, the analytical expression of the true minimum time is also provided for the time-dependent Hamiltonians with time-independent eigenstates.

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Mao Zhang, Huai-Ming Yu, Jing Liu. 2023-01-02. Quantum speed limit for complex dynamics. https://doi.org/10.1038/s41534-023-00768-8

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