Optoelectrostatic storage ring for polar molecules from supersonic expansion

Cold molecules are desired in a wide range of research areas, like precision measurement of physical constants, high-resolution spectroscopy, and cold collisions. Scientific interest in the generation and manipulation of cold molecules has been strong for decades. Here we theoretically investigate the dynamics of an optoelectrostatic storage ring for polar molecules, which is composed of an orbiting laser beam and an electrostatic quadrupole ring. The potentials of water molecules experienced in the combined optical and electrical fields are first calculated and a three-dimensional (3D) hybrid potential well for molecules of interest is formed in the focus spot of the red-detuned laser beam. The behavior of motional water molecules under the influence of the decelerating hybrid potential well is then investigated. Later, the deceleration and trapping processes of water molecules from supersonic expansion in the hybrid potential well are numerically simulated and corresponding results are presented. Our study indicates that this optoelectrostatic storage ring, featuring a 3D potential well of controllable orbiting speed, can serve as a good platform for production and manipulation of cold polar molecules and should have important applications in the related research areas.