Observation of Rydberg blockade between two atoms

TL;DR

This paper reports the experimental observation of Rydberg blockade between two rubidium atoms separated by over 10 micrometers, confirming long-range dipole-dipole interactions prevent simultaneous excitation.

Contribution

First experimental demonstration of Rydberg blockade between two atoms at such a large separation, validating theoretical models of dipole-dipole interactions.

Findings

Double excitation probability of ~30%

Agreement with theoretical dipole-dipole interaction model

Observation of blockade effect at >10 μm distance

Abstract

We demonstrate experimentally that a single Rb atom excited to the $79d_{5/2}$ level blocks the subsequent excitation of a second atom located more than $10 \mu\rm m$ away. The observed probability of double excitation of $\sim 30%$ is consistent with a theoretical model based on calculations of the long range dipole-dipole interaction between atoms.