Rydberg-Rydberg collisions in a cold, dense Rydberg gas can lead to the conversion of
internal energy into center-of-mass energy of the colliding atoms, resulting in Rydberg-atom …

We employ ensembles of cold Rydberg-atom gases produced via photo-excitation of laser-
cooled atom clouds in order to investigate collision-induced dynamics, excitation blockades …

Using state-selective field ionization, the state distributions of Rydberg atoms in cold
Rydberg gases are measured for various initially excited Rydberg levels, populations, and …

Cold, dense Rydberg gases produced in a cold-atom trap are investigated using
spectroscopic methods and time-resolved electron counting. Optical excitation on the …

Dense samples of cold Rydberg atoms have previously been observed to spontaneously
evolve to a plasma, despite the fact that each atom may be bound by as much as 100 cm− 1 …

We report clear evidence of the role of the attractive dipole-dipole interaction in Penning
ionization of Rydberg atoms, leading to the formation of an ultracold plasma. Penning …

The experiments reported here show that the dipole-dipole interaction, the fundamental
interaction between the cold Rydberg atoms, is the dominant initial ionization mechanism for …

Within a dense environment (ρ≈ 10 14 atoms/cm 3) at ultracold temperatures (T< 1 μ K), a
single atom excited to a Rydberg state acts as a reaction center for surrounding neutral …

Publisher Summary Within the past few years, Rydberg atoms have been the subject of
numerous experimental investigations. A major stimulus for this activity has been the …

A Rydberg gas of xenon, entrained in a supersonic atomic beam, evolves slowly to form an
ultracold plasma. In the early stages of this evolution, when the free-electron density is low …