Caught in a trap

Bob B. Buckley, D. D. Awschalom

Taro Hasegawa, T. Shimizu

Barium ions are trapped simultaneously with laser-cooled magnesium ions in a radio-frequency (RF) trap and cooled sympathetically. The barium ions are produced by charge transfer with the magnesium ions and are caught in a shallow trapping potential. The temperature of the trapped barium ions is measured, and it is confirmed that sympathetic cooling is effective. It is demonstrated that charge-transfer ionization is applicable to produce other ion species.

J. Morzinski, Parminder S. Bhatia, M. S. Shahriar

We present a technique to stabilize in an atomic transition the chirping frequency of a narrow-band semiconductor diode laser. The technique is demonstrated to chirp-cool Rb85 atoms used for loading a magneto-optical trap. The stabilization process eliminates long-term fluctuations and drifts in the number of atoms caught in the trap. This is a simple, easy-to-implement, and robust method for wide range of laser cooling experiments employing frequency chirping.