Towards Quantum Gas Microscopy of Ultracold Molecules

Abstract

Ultracold atoms in optical lattices allow the study of large ensembles of strongly interacting quantum particles in an isolated environment. They are widely used as analogue quantum simulators to study phenomena from many areas of physics in a setting with high tunability and versatile detection methods. Many experiments now detect and control the atoms with single-site resolution in what are known as quantum gas microscopes. By extending these techniques to ultracold molecules it will be possible to extend the range of interparticle interactions and increase the diversity of types of quantum systems which can be studied in optical lattices.

This thesis reports on the construction of a new apparatus which is designed to realise a quantum gas microscope for ultracold 87Rb 133Cs molecules. The apparatus consists of two trapping regions to provide sufficient optical access for the high numerical aperture lens and three-dimensional optical lattice required for quantum gas microscopy. By using degenerate Raman sideband cooling and fast moving-lattice optical transport followed by evaporation in an optical dipole trap we are able to cool both species to quantum degeneracy while maintaining a relatively fast repetition rate.

Using a three-dimensional optical lattice we observe the superfluid to Mott insulator transition in 133Cs, demonstrating the ability to reach the strongly correlated regime. The final section of this thesis reports on preliminary experiments on fluorescence imaging of 133Cs atoms pinned to lattice sites, which will pave the way for the implementation of quantum gas microscopy of molecules.