All-optical measurement of Rydberg state lifetimes

TL;DR

This paper introduces an all-optical technique to measure Rydberg state lifetimes in ultracold rubidium atoms, revealing environmental effects and interaction-induced ionization, with potential applications in quantum information science.

Contribution

The paper presents a novel all-optical method for measuring Rydberg state lifetimes, enabling precise decay curve reconstruction without destructive techniques.

Findings

Lifetime increases at lower temperatures due to reduced black body radiation.

Ionization and lifetime reduction observed for interacting Rydberg states.

Method successfully applied to dilute ultracold rubidium clouds.

Abstract

We have developed an all-optical method for measuring the lifetimes of $n S$ and $n D$ Rydberg states and demonstrate its capabilities with measurements on a dilute cloud of ultracold ${}^{87}$Rb atoms in a cryogenic environment. The method is based on the time-resolved observation of resonant light absorption by ground state atoms and selective transfer of Rydberg atoms into the ground state at varying delay times in order to reconstruct Rydberg decay curves. Our measurements of the ${}^{87}$Rb $30S_{1/2}$ state indicate an increase of the lifetime at lowered environment temperatures, as expected due to decreased black body radiation. For the $38D_{5/2}$ state with an attractive dipole-dipole interaction, ionization and lifetime reduction due to collisional effects are observed.