Microwave shielding of ultracold polar molecules

TL;DR

This paper demonstrates microwave-induced repulsive interactions to shield ultracold polar molecules, reducing loss rates and enhancing elastic collisions, with magnetic fields further improving stability under realistic conditions.

Contribution

It introduces a novel microwave shielding mechanism that differs from previous proposals and does not rely on canceling dipole-dipole interactions.

Findings

Microwave shielding suppresses loss mechanisms in ultracold polar molecules.

Magnetic fields can reduce loss rates below 10^-14 cm^3 s^-1.

The proposed mechanism differs from earlier models and does not require canceling dipole interactions.

Abstract

We use microwaves to engineer repulsive long-range interactions between ultracold polar molecules. The resulting shielding suppresses various loss mechanisms and provides large elastic cross sections. Hyperfine interactions limit the shielding under realistic conditions, but a magnetic field allows suppression of the losses to below 10-14 cm3 s-1. The mechanism and optimum conditions for shielding differ substantially from those proposed by Gorshkov et al. [Phys. Rev. Lett. 101, 073201 (2008)], and do not require cancelation of the long-range dipole-dipole interaction that is vital to many applications.