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arXiv · 2607.11282

Barium-based Rydberg atom quantum technologies with long Rydberg coherence

Xiao-Feng Shi
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Abstract

The short Doppler-limited coherence time of the laser-excited Rydberg state, usually orders of magnitude shorter than the lifetime of the Rydberg state, hinders the Rydberg-mediated quantum technologies. Here, we show that a 649~nm~$-$~658~nm two-photon excitation of the $6sng~^1G_4$ Rydberg state from a long-lived d-orbital clock state of barium can be achieved with a two-photon wavevector that is tiny, which effectively removes the Doppler-limited decoherence. Moreover, the $6sng~^1G_4$ Rydberg state has strong dipole-dipole interaction due to small F\"{o}rster defect with nearby Rydberg states and possesses long radiative lifetime. These can benefit quantum computing based on individually trapped neutral atoms, and can enable long-lived Rydberg polaritons in atomic media, which brings fresh opportunities in all-optical quantum information.

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Xiao-Feng Shi. 2026-07-13. Barium-based Rydberg atom quantum technologies with long Rydberg coherence. https://doi.org/10.1103/bbv3-d4ch

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