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arXiv · 2101.01936

Quantum nonlinear optics based on two-dimensional Rydberg atom arrays

Abstract

Here, we explore the combination of sub-wavelength, two-dimensional atomic arrays and Rydberg interactions as a powerful platform to realize strong, coherent interactions between individual photons with high fidelity. In particular, the spatial ordering of the atoms guarantees efficient atom-light interactions without the possibility of scattering light into unwanted directions, for example, allowing the array to act as a perfect mirror for individual photons. In turn, Rydberg interactions enable single photons to alter the optical response of the array within a potentially large blockade radius $R_b$, which can effectively punch a large "hole" for subsequent photons. We show that such a system enables a coherent photon-photon gate or switch, with an error scaling $\sim R_b^{-4}$ that is significantly better than the best known scaling in a disordered ensemble. We also investigate the optical properties of the system in the limit of strong input intensities. Although this a priori represents a complicated, many-body quantum driven dissipative system, we find that the behavior can be captured well by a semi-classical model based on holes punched in a classical mirror.

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Mariona Moreno-Cardoner, Daniel Goncalves, Darrick E. Chang. 2021-01-06. Quantum nonlinear optics based on two-dimensional Rydberg atom arrays. https://doi.org/10.1103/physrevlett.127.263602

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