Deeply bound ultracold molecules in an optical lattice

TL;DR

This paper reports the successful transfer and trapping of ultracold molecules in a deeply bound state within an optical lattice, achieving high transfer efficiency and demonstrating trapping stability, paving the way for ground state transfer.

Contribution

The study demonstrates efficient transfer of ultracold molecules into a deeply bound rovibrational level in an optical lattice with high efficiency, and characterizes their trapping properties.

Findings

25% overall molecule creation efficiency

>80% transfer efficiency to |v=73,J=2>

20 ms trapping time at 15 recoil energies

Abstract

We demonstrate efficient transfer of ultracold molecules into a deeply bound rovibrational level of the singlet ground state potential in the presence of an optical lattice. The overall molecule creation efficiency is 25%, and the transfer efficiency to the rovibrational level |v=73,J=2> is above 80%. We find that the molecules in |v=73,J=2> are trapped in the optical lattice, limited by optical excitation by the lattice light. The molecule trapping time for a lattice depth of 15 atomic recoil energies is about 20 ms. We determine the trapping frequency by the lattice phase and amplitude modulation technique. It will now be possible to transfer the molecules to the rovibrational ground state |v=0,J=0> in the presence of the optical lattice.