Observation of Microwave Shielding of Ultracold Molecules

TL;DR

This paper demonstrates how microwave radiation can be used to control interactions between ultracold molecules, significantly reducing inelastic collisions and enabling longer-lived molecular samples for quantum science applications.

Contribution

It introduces a method to engineer and tune interaction potentials between ultracold molecules using microwave shielding, validated by experimental results and theoretical calculations.

Findings

Microwave shielding suppresses inelastic loss rates by a factor of six.

Proper microwave frequency and power create an effective repulsive shield.

The method enables longer-lived, dense ultracold molecular samples.

Abstract

Harnessing the potential wide-ranging quantum science applications of molecules will require control of their interactions. Here, we use microwave radiation to directly engineer and tune the interaction potentials between ultracold calcium monofluoride (CaF) molecules. By merging two optical tweezers, each containing a single molecule, we probe collisions in three dimensions. The correct combination of microwave frequency and power creates an effective repulsive shield, which suppresses the inelastic loss rate by a factor of six, in agreement with theoretical calculations. The demonstrated microwave shielding shows a general route to the creation of long-lived, dense samples of ultracold molecules and evaporative cooling.