Cooperative optical non-linearity due to dipolar interactions in an ultra-cold Rydberg ensemble

Understand

We demonstrate a cooperative optical non-linearity caused by dipolar interactions between Rydberg atoms in an ultra-cold atomic ensemble.

• By coupling a probe transition to the Rydberg state we map the strong dipole-dipole interactions between Rydberg pairs onto the optical field.
• We characterize the non-linearity as a function of electric field and density, and demonstrate the enhancement of the optical non-linearity due to cooperativity.