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arXiv · 2006.06329

Subradiant emission from regular atomic arrays: universal scaling of decay rates from the generalized Bloch theorem

Yu-Xiang Zhang·Klaus Mølmer
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Abstract

The Hermitian part of the dipole-dipole interaction in infinite periodic arrays of two-level atoms yields an energy band of singly excited states. In this Letter, we show that a dispersion relation, $\omega_k-\omega_{k_\ex} \propto (k-k_{\ex})^s$, near the band edge of the infinite system leads to the existence of subradiant states of finite one-dimensional arrays of $N$ atoms with decay rates scaling as $N^{-(s+1)}$. This explains the recently discovered $N^{-3}$ scaling and it leads to the prediction of power law scaling with higher power for special values of the lattice period. For the quantum optical implementation of the Su-Schrieffer-Heeger (SSH) topological model in a dimerized emitter array, the band-gap-closing inherent to topological transitions changes the value of $s$ in the dispersion relation and alters the decay rates of the subradiant states by many orders of magnitude.

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Yu-Xiang Zhang, Klaus Mølmer. 2020-06-11. Subradiant emission from regular atomic arrays: universal scaling of decay rates from the generalized Bloch theorem. https://doi.org/10.1103/physrevlett.125.253601

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