2025 Theses Doctoral

From laser cooled molecules to novel quantum matter

Sun, Qi

Recent achievements in quantum-state control of atoms and molecules have demonstrated their potential for quantum information science, ultracold chemistry, and precision measurements. Meanwhile, the fact that only a third of all the elements have been optically trapped indicates a huge room for exploration. Among the optically untrapped elements, hydrogen stands out due to its simplicity, offering a uniquely ideal platform for rigorous comparisons between theoretical predictions and experimental results. Calcium monohydride is favorable for laser cooling, and has a unique double-well potential that is proposed to enable controlled photodissociation.

In this thesis, I will present our experimental efforts and theoretical studies aimed at trapping and photodissociating CaH and CaD molecules to generate ultracold hydrogen and deuterium clouds. These investigations pave the way for a universal platform to produce exotic ultracold atomic gases, with profound implications for fundamental science and advancements in quantum technology.