arXiv:1311.1593 · Physical Review A

Quantum speedup in a memory environment

Zhenyu Xu, Shunlong Luo, W. L. Yang, Chen Liu, Shiqun Zhu

Published Jan 8, 2014• 156 citations

Abstract

Memory (non-Markovian) effect is found to be able to accelerate quantum evolution [S. Deffner and E. Lutz, Phys. Rev. Lett. 111, 010402 (2013).]. In this work, for an atom in a structured reservoir, we show that the mechanism for the speedup is not only related to non-Markovianity but also to the population of excited states under a given driving time. In other words, it is the competition between non-Markovianity and population of excited states that ultimately determines the acceleration of quantum evolution in memory environments. A potential experimental realization for verifying the above phenomena is discussed by using a nitrogen-vacancy center embedded in a planar photonic crystal cavity under current technologies.

DOI: 10.1103/physreva.89.012307

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