Abstract

Laser-cooled atoms can be excited into Rydberg states to study Rydberg gases at high densities and low atomic velocities.^1,2 Dense clouds of such atoms undergo virtually complete ionization when their density exceeds a critical value dependent on the principal quantum number n.³ We report a new regime in which the excited Rydberg population spontaneouslyevolves into long- lived high-l states, the lifetimes of which exceed the natural lifetimes of the initially excited Rydberg levels by two orders of magnitude.

© 2001 Optical Society of America