We have built an apparatus where we trap two species of ultracold atoms, with the goal of associating atoms and creating heteronuclear polar molecules which have a permanent electric dipole moment. An ensemble of such molecules interact via the dipole-dipole interaction, which is relatively long-range and anisotropic. Our interest is in understanding such systems. In our lab, we have produced ultracold lithium atoms in a magneto-optical trap together with ultracold cesium atoms in a magneto-optical trap. Subsequently, we will transfer the ultracold atoms of both species to a common optical dipole trap and associate them to form molecules. Our apparatus has a time of flight mass spectrometer which should be able to detect molecular ions formed by photoionization of ultracold molecules.  We have also trapped ions in our apparatus. Check our JCP 2024 paper for details of the apparatus. 

See review articles to know more about this field:
Cold and ultracold molecules in the twenties
Quantum science with optical tweezer arrays of ultracold atoms and molecules
Ultracold Molecules under Control!
Cold hybrid ion-atom systems
Quantum dynamics of single trapped ions
Quantum computing with trapped ions
Trapped-ion quantum computing: Progress and challenges

The cesium atom is of interest in the field of precision measurement. The atomic structure calculations of cesium have reached remarkable accuracy (perhaps placed in the third position, after atomic hydrogen and helium) and their comparison with high precision experimental measurements may lead to the discovery of new phenomena or effects. We have developed a technique based on Doppler-free two-photon spectroscopy to measure the hyperfine splitting (hfs) of excited states with very high  precision. We have measured the hfs of the 7d states, improving over earlier reports by 10 times. Our technique allowed the measurement of systematic effects such as collisional shift and ac Stark shift, which could then be corrected for. We plan to continue such measurements with other electronic states.  

Precise control and manipulation of ultracold molecules, which have a plethora of electronic, vibrational and rotational degrees of freedom, can open exciting new research directions. In particular, ultracold polar molecules, with strong anisotropic dipole-dipole interaction, are interesting systems for studying quantum state controlled chemical reactions, novel quantum phases and quantum information. One such molecule is the LiRb molecule that has a substantial electric dipole moment of 4.1 Debye in its vibronic ground state. We were the first group to create ultracold polar LiRb molecules. In these experiments, carried out at Purdue University, LiRb molecules were created using photoassociation -  a technique where a laser photon is used to bind ultracold atoms to produce a molecule.