arXiv:2201.12575 · Physical Review Research

Giant atoms with time-dependent couplings

Lei Du, Yao-Tong Chen, Yan Zhang, Yong Li

Published Jun 7, 2022• 63 citations

Abstract

We study the decay dynamics of a two-level giant atom that is coupled to a waveguide with time-dependent coupling strengths. In the non-Markovian regime where the retardation effect cannot be ignored, we show that the dynamics of the atom depends on the atom-waveguide coupling strengths at an earlier time. This allows one to tailor the decay dynamics of the giant atom and even realize a stationary population revival with appropriate coupling modulations. Moreover, we demonstrate the possibility of simulating the quantum Zeno and quantum anti-Zeno effects in the giant-atom model with periodic coupling quenches. These results have potential applications in quantum information processing and quantum network engineering.

DOI: 10.1103/physrevresearch.4.023198

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