Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:0910.1771 · Physical Review A

Spectral linewidth broadening from pair fluctuations in a frozen Rydberg gas

B. Sun, F. Robicheaux

Published Oct 6, 2008• 33 citations
arXivHTMLPDF

Abstract

Spectral linewidth broadening in Rydberg gases, a phenomenon previously attributed to the many-body effect, was observed experimentally almost a decade ago. The observed linewidth was typically 80--100 times larger than the average interaction strength predicted from a binary interaction. The interpretation of such a phenomenon is usually based on the so-called diffusion model, where the linewidth broadening mostly originates from the diffusion of excitations. We present a model calculation to show that diffusion is not the main mechanism of the linewidth broadening. We find that the rare pair fluctuation at small separation is the dominant factor contributing to this broadening. Our results give a width of about 20--30 times larger than the average interaction strength. More importantly, by turning off the diffusion process, we do not observe an order-of-magnitude change in the spectral linewidth.

DOI
10.1103/physreva.78.040701

Related papers

Simulations of prompt many-body ionization in a frozen Rydberg gas

F. Robicheaux, M. M. Goforth, M. A. Phillips

The results of a theoretical investigation of prompt many-body ionization are reported. Our calculations address an experiment that reported ionization in Rydberg gases for densities two orders of magnitude less than expected from ionization between pairs of atoms. The authors argued that the results were due to the simultaneous interaction between many atoms. We performed classical calculations for many interacting Rydberg atoms with the ions fixed in space and have found that the many-atom interaction does allow ionization at lower densities than estimates from two-atom interactions. However, we found that the density fluctuations in a gas play a larger role. These two effects are an order of magnitude too small to account for the experimental results suggesting at least one other mechanism strongly affects ionization.

arXiv:1406.3569•Physical Review A•Aug 20, 2014•9 citations

Anomalous Broadening in Driven Dissipative Rydberg Systems

Elizabeth A. Goldschmidt, Thomas Boulier, Roger C. Brown +5 more

We observe interaction-induced broadening of the two-photon 5s-18s transition in ^{87}Rb atoms trapped in a 3D optical lattice. The measured linewidth increases by nearly 2 orders of magnitude with increasing atomic density and excitation strength, with corresponding suppression of resonant scattering and enhancement of off-resonant scattering. We attribute the increased linewidth to resonant dipole-dipole interactions of 18s atoms with blackbody induced population in nearby np states. Over a range of initial atomic densities and excitation strengths, the transition width is described by a single function of the steady-state density of Rydberg atoms, and the observed resonant excitation rate corresponds to that of a two-level system with the measured, rather than natural, linewidth. The broadening mechanism observed here is likely to have negative implications for many proposals with coherently interacting Rydberg atoms.

arXiv:1510.08710•Physical Review Letters•Mar 16, 2016•110 citations

Controlled many-body interactions in a frozen Rydberg gas

I. Mourachko, Wenhui Li, Thomas F. Gallagher

Previous resonant dipole-dipole energy-transfer experiments of cold Rydberg gases [Anderson et al., Phys. Rev. Lett. 80, 249 (1998); Mourachko et al., Phys. Rev. Lett. 80, 253 (1998)] have been interpreted as providing evidence of many-body, as opposed to purely binary, effects. Here we separate two-body and many-body interactions by introducing an additional Rydberg state, which does not participate directly in the energy-transfer process, but is strongly coupled to one of the final states. We observe broadening of the energy-transfer resonances due to this added Rydberg state, which clearly demonstrates the many-body nature of the dipole-dipole interactions in such a system.

Physical Review A•Sep 13, 2004•54 citations

Many-Body Effects in a Frozen Rydberg Gas

I. Mourachko, D. Comparat, F. De Tomasi +4 more

We studied the properties of a cold ( $\ensuremath{\sim}100\ensuremath{\mu}\mathrm{K}$) and dense ( $\ensuremath{\sim}{10}^{8--10}{\mathrm{cm}}^{\ensuremath{-}3}$) atomic Rydberg Cs gas, and found that the observed widths and shapes of resonances in population transfers cannot be explained in the framework of a usual gas model. We propose a ``frozen Rydberg gas'' model, where the interplay between two-body and many-body phenomena affects in an unexpected way the width and the shape of spectral lines.

Physical Review Letters•Jan 12, 1998•337 citations

Spectral line broadening due to the interaction between very excited atoms: 'the dense Rydberg gas'

J. M. Raimond, Guy Vitrant, S. Haroche

The authors report the first observation of spectral line perturbations, due to van der Waals coupling between very excited atoms, in a sample where the average interatomic distance is about 15 times the Rydberg atom radius. Broadenings of the order of intervals between adjacent lines reveal Rydberg-Rydberg couplings no longer negligible compared with the atomic binding energy. The authors analyse the excitation mechanism of this 'dense Rydberg gas' by laser light non-resonant for the unperturbed atoms.

Journal of Physics B Atomic and Molecular Physics•Nov 14, 1981•81 citations

Suppression of Excitation and Spectral Broadening Induced by Interactions in a Cold Gas of Rydberg Atoms

Kilian Singer, M. Reetz‐Lamour, Thomas Amthor +2 more

We report on the observation of ultralong range interactions in a gas of cold rubidium Rydberg atoms. The van der Waals interaction between a pair of Rydberg atoms separated as far as 100,000 Bohr radii features two important effects: spectral broadening of the resonance lines and suppression of excitation with increasing density. The density dependence of these effects is investigated in detail for the S- and P-Rydberg states with principal quantum numbers n approximately 60 and n approximately 80 excited by narrow-band continuous-wave laser light. The density-dependent suppression of excitation can be interpreted as the onset of an interaction-induced local blockade.

arXiv:physics/0404075•Physical Review Letters•Oct 13, 2004•411 citations
Spectral linewidth broadening in Rydberg gases, a phenomenon previously attributed to the many-body effect, was observed experimentally almost a decade ago. The observed linewidth was typically 80--100 times larger than the average interaction strength predicted from a binary interaction. The interpretation of such a phenomenon is usually based on the so-called diffusion model, where the linewidth broadening mostly originates from the diffusion of excitations. We present a model calculation to show that diffusion is not the main mechanism of the linewidth broadening. We find that the rare pair fluctuation at small separation is the dominant factor contributing to this broadening. Our results give a width of about 20--30 times larger than the average interaction strength. More importantly, by turning off the diffusion process, we do not observe an order-of-magnitude change in the spectral linewidth.
The results of a theoretical investigation of prompt many-body ionization are reported. Our calculations address an experiment that reported ionization in Rydberg gases for densities two orders of magnitude less than expected from ionization between pairs of atoms. The authors argued that the results were due to the simultaneous interaction between many atoms. We performed classical calculations for many interacting Rydberg atoms with the ions fixed in space and have found that the many-atom interaction does allow ionization at lower densities than estimates from two-atom interactions. However, we found that the density fluctuations in a gas play a larger role. These two effects are an order of magnitude too small to account for the experimental results suggesting at least one other mechanism strongly affects ionization.
We observe interaction-induced broadening of the two-photon 5s-18s transition in ^{87}Rb atoms trapped in a 3D optical lattice. The measured linewidth increases by nearly 2 orders of magnitude with increasing atomic density and excitation strength, with corresponding suppression of resonant scattering and enhancement of off-resonant scattering. We attribute the increased linewidth to resonant dipole-dipole interactions of 18s atoms with blackbody induced population in nearby np states. Over a range of initial atomic densities and excitation strengths, the transition width is described by a single function of the steady-state density of Rydberg atoms, and the observed resonant excitation rate corresponds to that of a two-level system with the measured, rather than natural, linewidth. The broadening mechanism observed here is likely to have negative implications for many proposals with coherently interacting Rydberg atoms.
Previous resonant dipole-dipole energy-transfer experiments of cold Rydberg gases [Anderson et al., Phys. Rev. Lett. 80, 249 (1998); Mourachko et al., Phys. Rev. Lett. 80, 253 (1998)] have been interpreted as providing evidence of many-body, as opposed to purely binary, effects. Here we separate two-body and many-body interactions by introducing an additional Rydberg state, which does not participate directly in the energy-transfer process, but is strongly coupled to one of the final states. We observe broadening of the energy-transfer resonances due to this added Rydberg state, which clearly demonstrates the many-body nature of the dipole-dipole interactions in such a system.
We studied the properties of a cold ( $\ensuremath{\sim}100\ensuremath{\mu}\mathrm{K}$) and dense ( $\ensuremath{\sim}{10}^{8--10}{\mathrm{cm}}^{\ensuremath{-}3}$) atomic Rydberg Cs gas, and found that the observed widths and shapes of resonances in population transfers cannot be explained in the framework of a usual gas model. We propose a ``frozen Rydberg gas'' model, where the interplay between two-body and many-body phenomena affects in an unexpected way the width and the shape of spectral lines.
The authors report the first observation of spectral line perturbations, due to van der Waals coupling between very excited atoms, in a sample where the average interatomic distance is about 15 times the Rydberg atom radius. Broadenings of the order of intervals between adjacent lines reveal Rydberg-Rydberg couplings no longer negligible compared with the atomic binding energy. The authors analyse the excitation mechanism of this 'dense Rydberg gas' by laser light non-resonant for the unperturbed atoms.
We report on the observation of ultralong range interactions in a gas of cold rubidium Rydberg atoms. The van der Waals interaction between a pair of Rydberg atoms separated as far as 100,000 Bohr radii features two important effects: spectral broadening of the resonance lines and suppression of excitation with increasing density. The density dependence of these effects is investigated in detail for the S- and P-Rydberg states with principal quantum numbers n approximately 60 and n approximately 80 excited by narrow-band continuous-wave laser light. The density-dependent suppression of excitation can be interpreted as the onset of an interaction-induced local blockade.