Coherent optical transfer of Feshbach molecules to a lower vibrational state

TL;DR

This paper demonstrates a high-efficiency, coherent transfer of ultracold Feshbach molecules into a lower vibrational state using STIRAP, achieving long lifetimes and quantum coherence, advancing molecular BEC research.

Contribution

It introduces a method for coherently transferring Feshbach molecules to lower vibrational states with high efficiency and long coherence times, crucial for molecular BEC development.

Findings

Transfer efficiency up to 87%

Molecular lifetimes of about 1 second

Successful creation of quantum superpositions

Abstract

Using the technique of stimulated Raman adiabatic passage (STIRAP) we have coherently transferred ultracold 87Rb2 Feshbach molecules into a more deeply bound vibrational quantum level. Our measurements indicate a high transfer efficiency of up to 87%. As the molecules are held in an optical lattice with not more than a single molecule per lattice site, inelastic collisions between the molecules are suppressed and we observe long molecular lifetimes of about 1 s. Using STIRAP we have created quantum superpositions of the two molecular states and tested their coherence interferometrically. These results represent an important step towards Bose-Einstein condensation (BEC) of molecules in the vibrational ground state.