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

Dipole-Dipole Interactions in a Cold Rydberg Gas

Brian Richards

Published Jul 25, 2017• 0 citations
Publisher

Abstract

We investigate the strength and effects of dipole-dipole interactions in a cold Rydberg atom system. Our experiments explore the absence of collective decay due to dipole-dipole interactions, characterize dipole-dipole interactions and their dependence on Rydberg atom density and atomic motion, and explore possible methods to control atom separation using dipole-dipole interactions.

DOI
10.18130/v3mb4v

Related papers

Dipole-Dipole Excitation and Ionization in an Ultracold Gas of Rydberg Atoms

Wenhui Li, Paul J. Tanner, Thomas F. Gallagher

In cold dense Rydberg atom samples, the dipole-dipole interaction strength is effectively resonant at the typical interatomic spacing in the sample, and the interaction has a 1/R3 dependence on interatomic spacing R. The dipole-dipole attraction leads to ionizing collisions of initially stationary atoms, which produces hot atoms and ions and initiates the evolution of initially cold samples of neutral Rydberg atoms into plasmas. More generally, the strong dipole-dipole forces lead to motion, which must be considered in proposed applications.

Physical Review Letters•May 4, 2005•248 citations

Influence of Dipole-Dipole Interaction on Electron Dynamics in a Cold Rydberg Gas

Tao Zhou

Electron dynamics in dipole-dipole (DD) coupled Rydberg atoms show some unique properties that do not exist in individual atoms.The goal of the research in this dissertation is to reveal and control the electron dynamics influenced by DD interaction in cold Rydberg gases.We have studied the decay of Rydberg excitations in a cold Rb gas and find no evidence for superradiance.The decay rates and population redistribution we observe are consistent with a model that considers only spontaneous emission from, and blackbody redistribution within, isolated atoms.Suppression of superradiant emission is likely due to variations in transition energies across the cold Rydberg atom sample.For initial s states, these variations are dominated by inhomogeneities in DD exchange interactions within the random ensemble.Such inhomogeneities will necessarily be present in any measurement involving a large number of atoms where the separation between atoms is not well defined.For initial p states, the suppression is likely due to a combination of DD exchange and electric field inhomogeneities.We have also explored the evolution of Rydberg wavepackets in the presence of strong dipole-dipole interactions in a frozen gas.The distribution of atom separations results in an inhomogeneity in the strength of the exchange coupling between neighboring atoms, causing a dephasing of the macroscopic coherence.We have also explored the mechanism of wavepacket coherence transfer from one Rydberg atom to a neighboring Rydberg atom via DD interactions utilizing the resonant DD coupling transition 25s33s↔24p34p.The phase-shift of the observed interference modulations in the 34p signal, relative to that in 25s, is a signature of wavepacket coherence transfer between atoms driven by electron correlations resulting from the controlled DD coupling between them.I would like to thank my advisor Professor Bob Jones for his guidance and help, not only in the detailed research performance but also in scientific ethics and methodology.He taught me how to operate most of the instruments as well as helped me fix failing apparatus.His rigorous, yet optimistic, working attitude always inspires me in my research.I don't remember how many times I have felt frustrated after getting nothing from a several days' experiment.At those times, I was always motivated and energetic from his guidance, constructive criticism and sincere encouragement, after even a short talk with him.The accomplishment of this dissertation involved a lot of his help, ranging from grammar checking, to language polishing, to error correction.I really feel grateful and fortunate to have worked with him for more than 5 years.Thanks also goes to my colleagues who have helped me in the research.Brian Richards worked with me a lot to fix failing instruments.He also programmed the data collection software.Sha Li taught me how to build setups to generate the THz radiation and build dye lasers.Kisra Nayomal Egodapitiya helped me adjust lasers and amplifiers many times.I also got invaluable inspiration from daily talks with them.

•Apr 27, 2016•0 citations

Creating Strontium Rydberg Atoms

Xinyue Zhang

Dipole-dipole interactions, the strongest, longest-range interactions possible between two neutral atoms, cannot be better manifested anywhere else than in a Rydberg atomic system. Rydberg atoms, having high principal quantum numbers n>>1 and dipole moments that scale as n^2, provide a powerful tool to examine dipole-dipole interactions. Therefore, we have studied the production and production rates of strontium Rydberg atoms created using two-photon excitation and have explored their properties in two distinct experiments. In the first experiment, very-high-n (n~300) Rydberg atoms are produced in a tightly collimated atomic beam allowing spectroscopic studies of their energy levels and their Stark effects. Simulations using a two-active-electron model, developed by our theoretical collaborators, allow detailed analysis of the results and are in remarkable agreement with the experimental results. The high density of Rydberg atoms achieved ~ 5*10^5 cm^(-3), in this experiment will allow studies of strongly interacting Rydberg-Rydberg systems. The second experiment, in which a cold strontium Rydberg gas is excited in a magneto-optic trap, features an imaging technique offering both spatial and temporal resolution. We use this technique to observe and study the evolution of an ultra-cold strontium Rydberg gas which reveals the importance of Rydberg-Rydberg interactions in the early stages of this evolution. Strongly interacting Rydberg gas provides an opportunity to realize a very strongly-correlated ultra-cold plasma.

•May 28, 2013•0 citations

Selective ejection of atoms in a cold Rydberg gas

L. Velazco, Juan A. Muniz, H. Failache +1 more

We experimentally demonstrate that pairs of Rydberg atoms in a cold gas can be targeted by a precisely tuned microwave field that induces a strong dipole-dipole interaction that selectively ejects these atoms from the gas.

Latin America Optics and Photonics Conference•Jan 1, 2024•0 citations

Dipole-dipole interactions experiment with a few cold Rb Rydberg atoms

Vasily M. Entin, Denis B. Tretyakov, Ilya I. Beterov +1 more

The aim of this paper is to realize excitation in a small volume, development of diagnostic methods for cold Rydberg atoms, spectroscopy of the microwave transitions between Rydberg states in the presence of the magneto-optical trap (MOT) quadrupole magnetic field, as well as observation of dipole-dipole interaction of a small number of Rydberg atoms.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 1, 2009•0 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
We investigate the strength and effects of dipole-dipole interactions in a cold Rydberg atom system. Our experiments explore the absence of collective decay due to dipole-dipole interactions, characterize dipole-dipole interactions and their dependence on Rydberg atom density and atomic motion, and explore possible methods to control atom separation using dipole-dipole interactions.
In cold dense Rydberg atom samples, the dipole-dipole interaction strength is effectively resonant at the typical interatomic spacing in the sample, and the interaction has a 1/R3 dependence on interatomic spacing R. The dipole-dipole attraction leads to ionizing collisions of initially stationary atoms, which produces hot atoms and ions and initiates the evolution of initially cold samples of neutral Rydberg atoms into plasmas. More generally, the strong dipole-dipole forces lead to motion, which must be considered in proposed applications.
Electron dynamics in dipole-dipole (DD) coupled Rydberg atoms show some unique properties that do not exist in individual atoms.The goal of the research in this dissertation is to reveal and control the electron dynamics influenced by DD interaction in cold Rydberg gases.We have studied the decay of Rydberg excitations in a cold Rb gas and find no evidence for superradiance.The decay rates and population redistribution we observe are consistent with a model that considers only spontaneous emission from, and blackbody redistribution within, isolated atoms.Suppression of superradiant emission is likely due to variations in transition energies across the cold Rydberg atom sample.For initial s states, these variations are dominated by inhomogeneities in DD exchange interactions within the random ensemble.Such inhomogeneities will necessarily be present in any measurement involving a large number of atoms where the separation between atoms is not well defined.For initial p states, the suppression is likely due to a combination of DD exchange and electric field inhomogeneities.We have also explored the evolution of Rydberg wavepackets in the presence of strong dipole-dipole interactions in a frozen gas.The distribution of atom separations results in an inhomogeneity in the strength of the exchange coupling between neighboring atoms, causing a dephasing of the macroscopic coherence.We have also explored the mechanism of wavepacket coherence transfer from one Rydberg atom to a neighboring Rydberg atom via DD interactions utilizing the resonant DD coupling transition 25s33s↔24p34p.The phase-shift of the observed interference modulations in the 34p signal, relative to that in 25s, is a signature of wavepacket coherence transfer between atoms driven by electron correlations resulting from the controlled DD coupling between them.I would like to thank my advisor Professor Bob Jones for his guidance and help, not only in the detailed research performance but also in scientific ethics and methodology.He taught me how to operate most of the instruments as well as helped me fix failing apparatus.His rigorous, yet optimistic, working attitude always inspires me in my research.I don't remember how many times I have felt frustrated after getting nothing from a several days' experiment.At those times, I was always motivated and energetic from his guidance, constructive criticism and sincere encouragement, after even a short talk with him.The accomplishment of this dissertation involved a lot of his help, ranging from grammar checking, to language polishing, to error correction.I really feel grateful and fortunate to have worked with him for more than 5 years.Thanks also goes to my colleagues who have helped me in the research.Brian Richards worked with me a lot to fix failing instruments.He also programmed the data collection software.Sha Li taught me how to build setups to generate the THz radiation and build dye lasers.Kisra Nayomal Egodapitiya helped me adjust lasers and amplifiers many times.I also got invaluable inspiration from daily talks with them.
Dipole-dipole interactions, the strongest, longest-range interactions possible between two neutral atoms, cannot be better manifested anywhere else than in a Rydberg atomic system. Rydberg atoms, having high principal quantum numbers n>>1 and dipole moments that scale as n^2, provide a powerful tool to examine dipole-dipole interactions. Therefore, we have studied the production and production rates of strontium Rydberg atoms created using two-photon excitation and have explored their properties in two distinct experiments. In the first experiment, very-high-n (n~300) Rydberg atoms are produced in a tightly collimated atomic beam allowing spectroscopic studies of their energy levels and their Stark effects. Simulations using a two-active-electron model, developed by our theoretical collaborators, allow detailed analysis of the results and are in remarkable agreement with the experimental results. The high density of Rydberg atoms achieved ~ 5*10^5 cm^(-3), in this experiment will allow studies of strongly interacting Rydberg-Rydberg systems. The second experiment, in which a cold strontium Rydberg gas is excited in a magneto-optic trap, features an imaging technique offering both spatial and temporal resolution. We use this technique to observe and study the evolution of an ultra-cold strontium Rydberg gas which reveals the importance of Rydberg-Rydberg interactions in the early stages of this evolution. Strongly interacting Rydberg gas provides an opportunity to realize a very strongly-correlated ultra-cold plasma.
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.