Ionization Detection of Ultracold Ground State Cesium Molecules

Photoassociation of ultracold atoms is an important method for producing stable ultracold molecules with extensive applications. Ion spectroscopy technique, which has higher sensitivity compared with trap loss spectroscopy and fragment spectroscopy, plays an important pole in the research of photoassociation spectroscopy. Based on ion spectroscopy technique, a complete experimental system is employed to produce and detect the ultracold ground state molecules, including the equipment of photoionization and time-of-fight mass spectroscopy. Ultracold ground state cesium molecules are demonstrated by the ionization detection technique. The number of the ground-state molecules produced in our MOT is measured. In addition, the relationship of the time interval of the cesium atom ion and the cesium molecular ion to the metal grid voltage is studied for the optimization of the experimental parameters.