A Mott Insulator of Ultracold Alkaline-Earth-Like Atoms

TL;DR

This paper reports the experimental observation of a superfluid to Mott insulator transition in a Bose-Einstein condensate of ytterbium atoms within an optical lattice, demonstrating a key quantum phase transition in ultracold atomic gases.

Contribution

First observation of a superfluid to Mott insulator transition in ytterbium Bose-Einstein condensates using optical lattices, highlighting potential for quantum simulation with alkaline-earth-like atoms.

Findings

Disappearance of interference patterns at high lattice depths

Confirmation of the MI phase transition in ytterbium BECs

Potential for studies combining MI states and ultranarrow optical transitions

Abstract

The transition from a superfluid to a Mott insulator (MI) phase has been observed in a Bose-Einstein condensate (BEC) of ytterbium (Yb) atoms in an optical lattice. An all-optically produced BEC of 174Yb atoms was loaded into three-dimensional optical lattices produced by a 532 nm laser beam. The interference pattern was measured after releasing the quantum gas from the trapping potential. As increasing the optical lattice depth, we observed the disappearance of the interference patterns, which is a signature of entering the MI regime. This result is an important step into studies by using a combination of the MI state and the ultranarrow optical transition of ultracold alkaline-earth-like atoms.