Pair Correlations and Photoassociation Dynamics of Two Atoms in an Optical Tweezer

TL;DR

This study explores the unique photoassociation behavior of two laser-cooled rubidium atoms in an optical tweezer, revealing non-exponential decay linked to pair correlations and demonstrating control over quantum states at the single-atom level.

Contribution

It provides the first detailed analysis of two-atom photoassociation dynamics, highlighting non-exponential decay due to pair correlations and bridging the understanding between two-atom and many-atom systems.

Findings

Non-exponential decay observed in two-atom photoassociation.

Decay behavior differs from many-atom ensembles governed by a single rate.

Control of single atoms reveals reaction dynamics inaccessible in many-atom systems.

Abstract

We investigate the photoassociation dynamics of exactly two laser-cooled $^{85}$Rb atoms in an optical tweezer and reveal fundamentally different behavior to photoassociation in many-atom ensembles. We observe non-exponential decay in our two-atom experiment that cannot be described by a single rate coefficient and find its origin in our system's pair correlation. This is in stark contrast to many-atom photoassociation dynamics, which are governed by exponential decay with a single rate coefficient. We also investigate photoassociation in a three-atom system, thereby probing the transition from two-atom dynamics to many-atom dynamics. Our experiments reveal additional reaction dynamics that are only accessible through the control of single atoms and suggest photoassociation could measure pair correlations in few-atom systems. It further showcases our complete control over the quantum state of individual atoms and molecules, which provides information unobtainable from many-atom experiments.