Rydberg Cold Collisions Dominated by Ultralong Range Potential

Abstract

In this work we measure the time evolution of the population resulting from energy-transfer collisions as a function of the energy difference between the entrance and exit collisional channels using a sample of cold Rydberg atoms produced in a rubidium magneto-optical trap. The $34S_{1/2}$ population, produced by collisions between atoms in the $33P_{3/2}$ state, is monitored as a function of time through the pulsed-field ionization technique. The experimental results are compared with a recent published model based on a two-body interaction considering an attractive potential [Phys. Rev. A 65, 023405 (2002)]; which is calculated according to a recent Letter by Boisseau et al. [Phys. Rev. Lett. 88, 133004 (2002)]. The agreement is remarkable, which suggests the existence of such ultralong range potential proposed by Boisseau et al.