Interplay between van der Waals and dipole-dipole interactions among Rydberg atoms

TL;DR

This paper investigates how black-body radiation influences Rydberg atoms by examining the interplay between van der Waals and dipole-dipole interactions, revealing their distinct roles in excitation dynamics and linewidth broadening.

Contribution

It demonstrates experimental evidence of black-body-induced dipole-dipole interactions in Rydberg atoms with significant van der Waals forces and introduces an enhanced model capturing their long-range effects.

Findings

Initial Rydberg excitation dominated by van der Waals interaction

Linewidth at later times dominated by dipole-dipole interaction

Potential applications in quantum simulation

Abstract

Coherently manipulating Rydberg atoms in mesoscopic systems has proven challenging due to the unwanted population of nearby Rydberg levels by black-body radiation. Recently, there have been some efforts towards understanding these effects using states with a low principal quantum number that only have resonant dipole-dipole interactions. We perform experiments that exhibit black-body-induced dipole-dipole interactions for a state that also has a significant van der Waals interaction. Using an enhanced rate-equation model that captures some of the long-range properties of the dipolar interaction, we show that the initial degree of Rydberg excitation is dominated by the van der Waals interaction, while the observed linewidth at later times is dominated by the dipole-dipole interaction. We also point out some prospects for quantum simulation.