Nonequilibrium phase transition in a dilute Rydberg Ensemble

Carr, C.; Ritter, R.; Wade, C.; Adams, C.S.; Weatherill, K.J.

Abstract

We demonstrate a nonequilibrium phase transition in a dilute thermal atomic gas. The phase transition, between states of low and high Rydberg occupancy, is induced by resonant dipole-dipole interactions between Rydberg atoms. The gas can be considered as dilute as the atoms are separated by distances much greater than the wavelength of the optical transitions used to excite them. In the frequency domain, we observe a mean-field shift of the Rydberg state which results in intrinsic optical bistability above a critical Rydberg number density. In the time domain, we observe critical slowing down where the recovery time to system perturbations diverges with critical exponent α=-0.53±0.10. The atomic emission spectrum of the phase with high Rydberg occupancy provides evidence for a superradiant cascade.

Citation

Carr, C., Ritter, R., Wade, C., Adams, C., & Weatherill, K. (2013). Nonequilibrium phase transition in a dilute Rydberg Ensemble. Physical Review Letters, 111(11), Article 113901. https://doi.org/10.1103/physrevlett.111.113901

• Journal Article Type: Article
• Publication Date: Jan 1, 2013
• Deposit Date: Aug 27, 2013
• Publicly Available Date: Oct 15, 2013
• Journal: Physical Review Letters
• Print ISSN: 0031-9007
• Electronic ISSN: 1079-7114
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 111
• Issue: 11
• Article Number: 113901
• DOI: https://doi.org/10.1103/physrevlett.111.113901
• Public URL: https://durham-repository.worktribe.com/output/1471443