UC Riverside

Laser cooling and trapping of atoms have revolutionized atomic physics with the realization to cool and trap atoms into the ultra-cold regime. This has led the precision of spectroscopy on atoms to an unprecedented level, which make cold atoms not only platforms to search for new physics and test fundamental laws of nature, but also ultra-precise tools to measure fundamental physical quantities such as time and magnetic fields. Cooling and trapping molecules into the cold and ultra-cold regime foresees similar revolutions. The rich internal energy structure and large permanent electric dipole moments of molecules enable a variety of applications beyond the realm of cold atoms, including searches for the electron electric dipole moment, studies of ultra-cold chemistry, and realizations of strongly interacting quan- tum many-body systems. However, the complex energy structure of molecules also render them difficult to laser cool and trap, especially at high densities. In this thesis, we present our progress on pursuing laser cooling and trapping of a new species, aluminum monochlo- ride(AlCl). The highly diagonal Franck-Condon factors(FCFs) and high scattering rate with large single photon recoil velocities owning to a cycling transition at DUV wavelength range make it a favorable candidate. We present our absorption spectroscopy on the A1Π ← X1Σ+ transition to extrapolate the molecular constants and estimate the Frank-Condon factors, and our effort to study the various targets for laser ablation production of AlCl to optimize its initial production. We also present our in-beam fluorescence spectroscopy to resolve the relevant hyperfine structure in the A1Π state in order to understand and construct optical cycling schemes.