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arXiv · 2408.17079

Demonstration of strong coupling of a subradiant atom array to a cavity vacuum

Bence Gábor·K. V. Adwaith·Dániel Varga·Bálint Sárközi·Árpád Kurkó·András Dombi·T. W. Clark·F. I. B. Williams·David Nagy·András Vukics·Peter Domokos
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Abstract

By considering linear scattering of laser-driven cold atoms inside an undriven high-finesse optical resonator, we experimentally demonstrate effects unique to a strongly coupled vacuum field. Arranging the atoms in an incommensurate lattice with respect to the radiation wavelength, the Bragg scattering into the cavity can be suppressed by destructive interference: the atomic array is subradiant to the cavity mode under transverse illumination. We show however, that strong collective coupling leads to a drastic modification of the excitation spectrum, as evidenced by well-resolved vacuum Rabi splitting in the intensity of the fluctuations. Furthermore, we demonstrate a significant polarization rotation in the linear scattering off the subradiant array via Raman scattering induced by the strongly coupled vacuum field.

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BibTeXRIS

Bence Gábor, K. V. Adwaith, Dániel Varga, Bálint Sárközi, Árpád Kurkó, András Dombi, T. W. Clark, F. I. B. Williams, David Nagy, András Vukics, Peter Domokos. 2024-08-30. Demonstration of strong coupling of a subradiant atom array to a cavity vacuum. https://doi.org/10.1140/epjqt/s40507-025-00401-x

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