Excitation transport in few-atom systems with resonant dipole-dipole interactions

We measure the transport of energy among the internal states of ultracold rubidium Rydberg atoms coupled by dipole-dipole exchange. In a magneto-optical trap, a static electric field of a few V/cm shifts the energy levels of the atoms. For a particular principal quantum number, $n$ , the angular momentum eigenstates $\ell > 4$ are nearly degenerate at zero electric field. At nonzero field, a manifold of equally spaced clusters form a ladder with each rung consisting of a set of closely spaced $m$ energy eigenstates. We excite Rydberg atoms to energy levels near the center of the manifold and allow them to exchange energy via resonant dipole-dipole interactions. We measure the time evolution as energy spreads away from the center of the manifold, which reveals that the system may fail to thermalize for long interaction times. A computational model that includes only a few essential features of the system qualitatively agrees with this result.We measure the transport of energy among the internal states of ultracold rubidium Rydberg atoms coupled by dipole-dipole exchange. In a magneto-optical trap, a static electric field of a few V/cm shifts the energy levels of the atoms. For a particular principal quantum number, $n$, the angular momentum eigenstates $\ell > 4$ are nearly degenerate at zero electric field. At nonzero field, a manifold of equally spaced clusters form a ladder with each rung consisting of a set of closely spaced $m$ energy eigenstates. We excite Rydberg atoms to energy levels near the center of the manifold and allow them to exchange energy via resonant dipole-dipole interactions. We measure the time evolution as energy spreads away from the center of the manifold, which reveals that the system may fail to thermalize for long interaction times. A computational model that includes only a few essential features of the system qualitatively agrees with this result.

arXiv:2407.21764Jul 31, 20240 citations

Breakup of Rydberg-blockaded atom clouds via dipole-dipole interactions

S. Möbius, Michael Genkin, Sebastian Wüster +2 more

We investigate resonant dipole-dipole interactions between two superatoms of different angular momentum, consisting of two Rydberg-blockaded atom clouds where each cloud carries initially a coherently shared single excitation. We demonstrate that the dipole-dipole interaction breaks up the superatoms by removing the excitations from the clouds. The dynamics is akin to an ensemble average over systems where only one atom per cloud participates in entangled motion and excitation transfer. Our findings should thus facilitate the experimental realization of adiabatic exciton transport in Rydberg systems by replacing single sites with atom clouds.We investigate resonant dipole-dipole interactions between two superatoms of different angular momentum, consisting of two Rydberg-blockaded atom clouds where each cloud carries initially a coherently shared single excitation. We demonstrate that the dipole-dipole interaction breaks up the superatoms by removing the excitations from the clouds. The dynamics is akin to an ensemble average over systems where only one atom per cloud participates in entangled motion and excitation transfer. Our findings should thus facilitate the experimental realization of adiabatic exciton transport in Rydberg systems by replacing single sites with atom clouds.

arXiv:1212.1267Physical Review AJul 30, 201317 citations

Excitations and transport in quantum liquids

David Pines

Lecture notes in physicsJan 1, 19814 citations

Excitations in Simple Atomic Ensembles

Springer eBooksOct 23, 20070 citations

Breaking the Dipole Blockade: Nearly Resonant Dipole Interactions in Few-Atom Systems

Thomas Pohl, P. R. Berman

A dipole blockade, in which Rydberg-atom-Rydberg-atom interactions inhibit all but a single collective Rydberg excitation, has been proposed as a mechanism to store and manipulate quantum information in mesoscopic ensembles. We investigate the excitation dynamics of a collection of a few atoms and show that they undergo an unexpected, qualitative change when the number of atoms increases from two to three. In particular, the combined action of three atoms, each of which pairwise would produce a blockade, can break the dipole blockade.A dipole blockade, in which Rydberg-atom-Rydberg-atom interactions inhibit all but a single collective Rydberg excitation, has been proposed as a mechanism to store and manipulate quantum information in mesoscopic ensembles. We investigate the excitation dynamics of a collection of a few atoms and show that they undergo an unexpected, qualitative change when the number of atoms increases from two to three. In particular, the combined action of three atoms, each of which pairwise would produce a blockade, can break the dipole blockade.

Physical Review LettersJan 7, 200983 citations

n

, the angular momentum eigenstates

\ell > 4

are nearly degenerate at zero electric field. At nonzero field, a manifold of equally spaced clusters form a ladder with each rung consisting of a set of closely spaced

m

energy eigenstates. We excite Rydberg atoms to energy levels near the center of the manifold and allow them to exchange energy via resonant dipole-dipole interactions. We measure the time evolution as energy spreads away from the center of the manifold, which reveals that the system may fail to thermalize for long interaction times. A computational model that includes only a few essential features of the system qualitatively agrees with this result.