Laser Cooling and Trapping of Sodium Atoms for Quantum Gas Microscopy of Ultracold NaRb Molecules

Goulven Quéméner, Romain Véxiau, Gao‐Ren Wang +5 more

Brian W. Petley

Geoffrey Z. Iwata

Ultracold molecules promise a revolutionary test bed for quantum science with applications ranging from experiments that probe the nature of our universe, to hosting new platforms for quantum computing. Cooling and trapping molecules in the ultracold regime is the first step to unlocking the wide array of proposed applications, and developing these techniques to control molecules is a key but challenging research field. In this thesis, we describe progress towards a new apparatus designed to cool and trap barium monohydride (BaH), a molecule that is amenable to laser cooling and has prospects as a precursor for ultracold atomic hydrogen. The same complexity that makes molecules interesting objects of study creates challenges for optical control. To mitigate some of these challenges, we first cool the molecules using cryogenic techniques and technologies. Our apparatus uses a cryogenic buffer gas to thermalize BaH within a contained cell. The molecules are extracted into a beam with millikelvin transverse temperature, and forward velocities <100 m/s. The BaH beam in this work is the brightest hydride beam to date, with molecule density and kinetic characteristics well suited for laser cooling and trapping.

Yukai Lu, Connor M. Holland, Lawrence W. Cheuk

Paul D. Lett, L. P. Ratliff, Mark E. Wagshul +2 more

Recent advances in laser cooling techniques have made possible a new type of spectroscopy. In the first experiments of this kind alkali atoms are laser cooled to temperatures around 1 mK and trapped, using laser fields, at densities around 1011 cm−3. Atoms colliding under such ultracold conditions can be resonantly photoassociated to bound states of the dimer molecules. These molecules can in turn be photoionized, providing a sensitive detection of the photoassociation spectrum and revealing in extremely high resolution the structure of the dimer molecules. The particular advantages of this technique include high resolution and signal‐to‐noise and the ability to reach extremely long range states of the molecule, accessible only through such slow collisions.

Vanderlei Salvador Bagnato, Luís Gustavo Marcassa

We present an overview of recent experiments we have done concerning the observation of photoassociative ionization in a cold sample of trapped sodium atoms. In a second stage, the process is used as a prototype to demonstrate the possibility of optical manipulation of interatomic collisions. This effect could be explored to manipulate the thermodynamical properties of a sample of degenerated quantum gas.