Directly trapping atoms in a U-shaped magneto-optical trap using a mini atom chip

摘要

We experimentally demonstrate the trapping of Rb-85 atoms directly on a chip-size U-shaped magneto-optical trap (U-MOT). The trap includes a U-shaped wire on the chip, two bias magnetic field coils and laser beams. The capture volume of the U-MOT is theoretically calculated, and the trap is experimentally realized. With 2A current applied to the U-shaped wire and 2-Gauss horizontal bias field, more than 2 x 10(6) atoms are trapped. In contrast with an ordinary mirror-MOT, this U-MOT captures atoms directly from the background, thus the trap size is greatly reduced. Based on this mini trap scheme, it is possible to realize a chip-size atom trap array for quantum information processing.