Dipole Blockade at Förster Resonances in High Resolution Laser Excitation of Rydberg States of Cesium Atoms

Abstract

High resolution laser excitation of $np$ Rydberg states of cesium atoms shows a dipole blockade at Förster resonances corresponding to the resonant dipole-dipole energy transfer of the $np+np\to ns+(n+1)s$ reaction. The dipole-dipole interaction can be tuned on and off by the Stark effect, and such a process, observed for relatively low $n(25–41)$, is promising for quantum gate devices. Both Penning ionization and saturation in the laser excitation can limit the range of observation of the dipole blockade.