Related papers: Ionization in a frozen Rydberg gas with attractive…
The dipole-dipole interaction among ultra-cold Rydberg atoms is simulated. We examine a general interaction scheme in which two atoms excited to the x and x' states are converted to y and y' states via a Forster resonance. The atoms are…
In the laser excitation of ultracold atoms to Rydberg states, we observe a dramatic suppression caused by van der Waals interactions. This behavior is interpreted as a local excitation blockade: Rydberg atoms strongly inhibit excitation of…
We calculate pair potential curves for interacting Rydberg atoms in a constant electric field and use them to determine the effective $C_3$ dipole-dipole and $C_6$ van der Waals coefficients. We compare the $C_3$ and $C_6$ with experiments…
A Rydberg gas of NO entrained in a supersonic molecular beam releases electrons as it evolves to form an ultracold plasma. The size of this signal, compared with that extracted by the subsequent application of a pulsed electric field,…
We present the theory for retarded resonance interaction between two identical atoms at arbitrary positions near a metal surface. The dipole-dipole resonance interaction force that binds isotropically excited atom pairs together in free…
Ionized geocosmic media parameters in a thermal and a subthermal range of energy have a number of unique features. The photoresonance plasma that is formed by optical excitation of the lowest excited (resonance) atomic states is one example…
Pulsed field ionization of high-$n$ (90 $\leq n \leq$ 150) manifold states in Rb Rydberg atoms has been investigated in high slew-rate regime. Two peaks in the field ionization spectra were systematically observed for the investigated $n$…
We present an overview of our recent investigations of long-range interactions in an ultracold Cs Rydberg gas. These interactions are studied by high-resolution photoassociation spectroscopy, using excitation close to one-photon transitions…
We report the creation of an ultracold neutral plasma by photoionization of laser-cooled xenon atoms. The charge carrier density is as high as 2 x 10^9 cm^-3, and the temperatures of electrons and ions are as low as 100 mK and 10 uK,…
Rydberg states of atoms are of great current interest for quantum manipulation of mesoscopic samples of atoms. Long-range Rydberg-Rydberg interactions can inhibit multiple excitations of atoms under the appropriate conditions. These…
Spontaneous avalanche to plasma splits the core of an ellipsoidal Rydberg gas of nitric oxide. Ambipolar expansion first quenches the electron temperature of this core plasma. Then, long-range, resonant charge transfer from ballistic ions…
We study two ions confined in a Penning trap. We show that electronically highly excited states exist in which an electron is delocalized among the two ions forming a giant molecule of several micrometer size. At energies close to the top…
An ultra-cold molecular plasma with extraordinarily long lifetime (~0.5 ms) is generated under strong collisional cooling conditions in the expansion region of a seeded supersonic jet expansion close to the nozzle. A resonant two-photon…
We present a method to control the shape and character of the interaction potential between cold atomic gases by weakly dressing the atomic ground state with a Rydberg level. For increasing particle densities, a crossover takes place from a…
The efficient suppression of Penning-ionizing collisions is a stringent requirement to achieve quantum degeneracy in metastable rare gases. Thus far, such loss processes have been avoided by electron-spin polarizing the collision partners.…
In plasmas at very low temperatures formation of neutral atoms is dominated by collisional three-body recombination, owing to the strong ~ T^(-9/2) scaling of the corresponding recombination rate with the electron temperature T. While this…
The effect of ionization and recombination processes on the electrical interactions between a pair of small charged particles in highly collisional plasmas is discussed. In particular, it is shown that these processes suppress the…
Laser cooled Rb atoms were optically excited to 46d Rydberg states. A microwave pulse transferred a fraction of the atoms to the 47p Rydberg state. The resonant electric dipole-dipole interactions between atoms in these two states were…
In this work, the stopping power of a partially ionized plasma is analyzed by means of free electron stopping and bound electron stopping. For the first one, the RPA dielectric function is used, and for the latter one, an interpolation of…
Clouds of ultracold strontium 5s48s 1S0 or 5s47d 1D2 Rydberg atoms are created by two photon excitation of laser cooled 5s2 1S0 atoms. The spontaneous evolution of the cloud of low orbital angular momentum (low-l) Rydberg states towards an…