Cold cesium molecules produced directly in a magneto–optical trap

We report on the observation of ultracold ground electric-state cesium molecules produced directly in a magneto- optical trap with a good signal-to-noise ratio. These molecules arise from the photoassociation of magneto-optical trap lasers and they are detected by resonantly enhanced multiphoton ionization technology. The production rate of ultracold cesium molecules is up to 4×10⁴ s^-1. We measure the characteristic time of the ground electric-state cesium molecules generated in the experiment and investigate the Cs₂⁺ molecular ion intensity as a function of the trapping laser intensity and the ionization pulse laser energy. We conclude that the production of cold cesium molecules may be enhanced by using appropriate experimental parameters, which is useful for future experiments involving the production and trapping of ultracold ground electric-state molecules.