Nonequilibrium phase transition in a dilute Rydberg Ensemble

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

doi:10.1103/physrevlett.111.113901

Nonequilibrium phase transition in a dilute Rydberg Ensemble

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

Authors

C. Carr

R. Ritter

C. Wade

C.S. Adams

Professor Kevin Weatherill k.j.weatherill@durham.ac.uk
Professor

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