Related papers: An echo experiment in a strongly interacting Rydbe…
We study the behavior of a Bose-Einstein condensate in which atoms are weakly coupled to a highly excited Rydberg state. Since the latter have very strong van der Waals interactions, this coupling induces effective, nonlocal interactions…
While dissipative Rydberg gases exhibit unique possibilities to tune dissipation and interaction properties, very little is known about the quantum many-body physics of such long-range interacting open quantum systems. We theoretically…
We experimentally study three-body energy exchange during Rydberg excitation near a two-body F\"orster resonance. By varying the excitation pulse duration or Rabi frequency, we control the process that causes the exchange. We demonstrate…
We study electromagnetically induced transparency of a ladder type configuration in ultracold atomic gases, where the upper level is an electronically highly excited Rydberg state. The strong two-body interaction in the Rydberg state leads…
In a recent work [Phys. Rev. Lett. 98, 023004 (2007)] we have investigated the influence of attractive van der Waals interaction on the pair distribution and Penning ionization dynamics of ultracold Rydberg gases. Here we extend this…
We propose a new all-optical method to image individual atoms within dense atomic gases. The scheme exploits interaction induced shifts on highly polarizable excited states, which can be spatially resolved via an electromagnetically induced…
Recent developments in the study of ultracold Rydberg gases demand an advanced level of experimental sophistication, in which high atomic and optical densities must be combined with excellent control of external fields and sensitive Rydberg…
An approach to fast entanglement generation based on Rydberg dephasing of collective excitations (spin-waves) in large, optically thick atomic ensembles is proposed. Long-range $1/r^3$ atomic interactions are induced by microwave mixing of…
We develop a theoretical approach for the dynamics of Rydberg excitations in ultracold gases, with a realistically large number of atoms. We rely on the reduction of the single-atom Bloch equations to rate equations, which is possible under…
In an ensemble of laser-driven atoms involving strongly interacting Rydberg states, the excitation probability is usually strongly suppressed. In contrast, here we identify a regime in which the steady-state Rydberg excited fraction is…
The collective excitations in ensembles of dissipative, laser driven ultracold atoms exhibit crystal-like patterns, a many-body effect of the Rydberg blockade mechanism. These crystalline structure are revealed in experiment from a…
Atom-atom interactions within a small volume were investigated through the excitation of ultracold Rb atoms. The application of microwaves enhances these interactions, causing the suppression of Rydberg state excitation. The suppression of…
We study the repulsive van der Waals interaction of cold rubidium $70S_{1/2}$ Rydberg atoms by analysis of time-delayed pair correlation functions. After excitation, Rydberg atoms are allowed to accelerate under the influence of the van der…
Interaction blockade occurs when strong interactions in a confined few-body system prevent a particle from occupying an otherwise accessible quantum state. Blockade phenomena reveal the underlying granular nature of quantum systems and…
The dipole blockade between Rydberg atoms has been proposed as a basic tool in quantum information processing with neutral atoms. Here we demonstrate experimentally the Rydberg blockade of two individual atoms separated by 4 $\mu$m.…
Due to the intrinsic strong blockaded interaction shifting the energy level of Rydberg state, the steady Rydberg probability may be substantially restrained to a low level, especially for atoms suffering from weak drivings. We report an…
We consider a system consisting of Rydberg dressed atoms interacting with BEC condensate of diatomic molecules. Using random phase approximation (RPA) we calculate the effective interactions between Rydberg atoms accounting for their Wan…
We present a detailed analysis of our recent observation of synchronous Rabi oscillations between the electronic ground state and Rydberg states in a mesoscopic ensemble containing roughly 100 ultracold atoms [M. Reetz-Lamour \textit{et…
In a laser-driven Rydberg gas the strong interaction between atoms excited to Rydberg states results in the formation of collective excitations. Atoms within a so-called blockade volume share a single Rydberg excitation, which is…
We demonstrate the interaction-induced blockade effect in an ultracold $^{88}$Sr gas via studying the time dynamics of a two-photon excitation to the triplet Rydberg series $5\mathrm{s}n\mathrm{s}\, ^3\textrm{S}_1$ for five different…