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arXiv · 2006.15623

Quantum Engineering of Superdark Excited States in Arrays of Atoms

A. A. Makarov·V. I. Yudson
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Abstract

We suggest a regular method of achieving an extremely long lifetime of a collective singly excited state in a generic small-size ensemble of N identical atoms. The decay rate Γ_N of such a `superdark' state can be as small as Γ_N \propto Γ(r/λ)^{2(N-1)} (Γis the radiative decay rate of an individual atom, r and λare the system size and the wavelength of the radiation, respectively), i.e., considerably smaller than in any of the systems suggested up to now. The method is based on a special fine tuning of the atomic Hamiltonian: namely, on a proper position-dependent adjustment of atomic transition frequencies. So chosen set of the control parameters is sufficient to ensure the minimum of the spontaneous decay rate of the engineered state in a generic ensemble of atoms (`qubits').

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A. A. Makarov, V. I. Yudson. 2020-06-28. Quantum Engineering of Superdark Excited States in Arrays of Atoms. https://doi.org/10.1103/physreva.102.053712

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