Ultracold Molecules in the Ro-Vibrational Triplet Ground State

TL;DR

This paper demonstrates the production of an ultracold gas of Rb2 molecules in the ro-vibrational triplet ground state with high transfer efficiency and long trapping lifetime, advancing control over ultracold molecular states.

Contribution

It introduces a highly efficient optical transfer method to produce ultracold Rb2 molecules in the triplet ground state within an optical lattice.

Findings

Achieved about 90% transfer efficiency to the ground state.

Trapped molecules exhibit a lifetime exceeding 200 ms.

Produced molecules are close to quantum degeneracy.

Abstract

We report here on the production of an ultracold gas of tightly bound Rb2 molecules in the ro-vibrational triplet ground state, close to quantum degeneracy. This is achieved by optically transferring weakly bound Rb2 molecules to the absolute lowest level of the ground triplet potential with a transfer efficiency of about 90%. The transfer takes place in a 3D optical lattice which traps a sizeable fraction of the tightly bound molecules with a lifetime exceeding 200 ms.