Observation of blackbody radiation enhanced superradiance in ultracold Rydberg gases

Hao, Liping; Bai, Zhengyang; Bai, Jingxu; Bai, Suying; Jiao, Yuechun; Huang, Guoxiang; Zhao, Jianming; Li, Weibin; Jia, Suotang

Abstract

An ensemble of excited atoms can synchronize emission of light collectively in a process known as superradiance when its characteristic size is smaller than the wavelength of emitted photons. The underlying superradiance depends strongly on electromagnetic (photon) fields surrounding the atomic ensemble. High mode densities of microwave photons from 300 K blackbody radiation (BBR) significantly enhance decay rates of Rydberg states to neighbouring states, enabling superradiance that is not possible with bare vacuum induced spontaneous decay. Here we report observations of the superradiance of ultracold Rydberg atoms embedded in a bath of room-temperature photons. The temporal evolution of the Rydberg |nD to |(n + 1)P superradiant decay of Cs atoms (n the principal quantum number) is measured directly in free space. Theoretical simulations confirm the BBR enhanced superradiance in large Rydberg ensembles. We demonstrate that the van der Waals interactions between Rydberg atoms change the superradiant dynamics and modify the scaling of the superradiance. In the presence of static electric fields, we find that the superradiance becomes slow, potentially due to many-body interaction induced dephasing. Our study provides insights into many-body dynamics of interacting atoms coupled to thermal BBR, and might open a route to the design of blackbody thermometry at microwave frequencies via collective, dissipative photon-atom interactions.

Citation

Hao, L., Bai, Z., Bai, J., Bai, S., Jiao, Y., Huang, G., …Jia, S. (2021). Observation of blackbody radiation enhanced superradiance in ultracold Rydberg gases. New Journal of Physics, 23(8), Article 083017. https://doi.org/10.1088/1367-2630/ac136c

• Journal Article Type: Article
• Acceptance Date: Jul 12, 2021
• Online Publication Date: Aug 13, 2021
• Publication Date: Aug 13, 2021
• Deposit Date: Jul 7, 2021
• Publicly Available Date: Aug 13, 2021
• Journal: New Journal of Physics
• Electronic ISSN: 1367-2630
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 23
• Issue: 8
• Article Number: 083017
• DOI: https://doi.org/10.1088/1367-2630/ac136c
• Keywords: General Physics and Astronomy
• Public URL: https://nottingham-repository.worktribe.com/output/5760101
• Publisher URL: https://iopscience.iop.org/article/10.1088/1367-2630/ac136c
• Additional Information: Article Title: Observation of blackbody radiation enhanced superradiance in ultracold Rydberg gases; Journal Title: New Journal of Physics; Article Type: paper; Copyright Information: © 2021 The Author(s). Published by IOP Publishing Ltd on behalf of the Institute of Physics and Deutsche Physikalische Gesellschaft; Date Received: 2021-04-03; Date Accepted: 2021-07-12; Online publication date: 2021-08-13