Generalized Coherent Quantum Speed Limits

• URL: http://arxiv.org/abs/2401.01746v1
• Date: Wed, 3 Jan 2024 13:49:15 GMT
• Title: Generalized Coherent Quantum Speed Limits
• Authors: Hai Wang and Xingze Qiu
• Abstract summary: We present two infinite families of coherent quantum speed limits (QSLs) for general unitary dynamics. We show that rapid quantum dynamics requires coherent superpositions of energy eigenstates, singling out coherence as a key resource for the evolution of quantum systems.
• Score: 2.7624036517702577
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We present two infinite families of coherent quantum speed limits (QSLs) for general unitary dynamics by employing the H\"older's inequality for matrix norms. Our approach clearly highlights the contribution of the coherence of the evolved states, and provides novel QSL bounds characterized by coherence measures based on Schatten $p$-norm or Hellinger distance. We illustrate our findings with relevant models, demonstrating our bounds are much tighter than the established ones and asymptotically saturable in the adiabatic limit. Our results show that rapid quantum dynamics requires coherent superpositions of energy eigenstates, singling out coherence as a key resource for the evolution of quantum systems.

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