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arXiv:1911.04839 · Journal of Physics B Atomic Molecular and Optical Physics

Quantum speed-up process of atom in dissipative cavity

Hong-Mei Zou, Jianhe Yang, Danping Lin, Mao-Fa Fang

Published Mar 24, 2020• 2 citations
arXivHTMLPDF

Abstract

Abstract In this work, we obtain an analytical representation of the density operator of an atom in a dissipative cavity when the reservoir is at zero temperature and the total number of excitations is N = 1. We also investigated the quantum speed limit time (QSLT) of the atom and the non-Markovianity in the dynamics process. The results show that the QSLT and the non-Markovianity can be effectively manipulated by the atom–cavity coupling and the reservoir parameters. Both of the atom–cavity coupling and the detuning can induce a sudden transition from Markovian to non-Markovian dynamics, and this transition is the main physical reason of the quantum speed-up process. The critical value of the sudden transition from no speed-up to speed-up the atom–cavity coupling and the reservoir parameters. The corresponding physical explanation is also provided for our results.

DOI
10.1088/1361-6455/ab82e2

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