Two-photon optical shielding of collisions between ultracold polar molecules

TL;DR

This paper introduces a two-photon optical shielding method to prevent collisional losses in ultracold polar molecules by engineering repulsive interactions, avoiding heating issues associated with one-photon schemes.

Contribution

It presents a novel two-photon transition scheme for optical shielding of ultracold molecules, improving upon previous methods by reducing photon scattering and heating.

Findings

Proposes a two-photon optical shielding protocol for ultracold molecules.

Demonstrates applicability to 23Na39K and other polar diatomic molecules.

Reduces heating compared to one-photon shielding methods.

Abstract

We propose a method to engineer repulsive long-range interactions between ultracold ground-state molecules using optical fields, thus preventing short-range collisional losses. It maps the microwave coupling recently used for collisional shielding onto a two-photon transition, and takes advantage of optical control techniques. In contrast to one-photon optical shielding [Phys. Rev. Lett. 125, 153202 (2020)], this scheme avoids heating of the molecular gas due to photon scattering. The proposed protocol, exemplified for 23Na39K, should be applicable to a large class of polar diatomic molecules.