Laser-cooling and magnetic trapping near 3 Tesla

Sung-Leung Ivan So

Harold J. Metcalf

Andrew J. Berglund, James L. Hanssen, Jabez J. McClelland

Jeffrey R. Guest, Jongsoo Choi, E. Hansis +2 more

Laser cooling and magnetic trapping of (85)Rb atoms have been performed in extremely strong and tunable magnetic fields, extending these techniques to a new regime and setting the stage for a variety of cold atom and plasma experiments. Using a superconducting Ioffe-Pritchard trap and an optical molasses, 2.4 x 10(7) atoms were laser cooled to the Doppler limit and magnetically trapped at bias fields up to 2.9 T. At magnetic fields up to 6 T, 3 x 10(6) cold atoms were laser cooled in a pulsed loading scheme. These bias fields are well beyond an order of magnitude larger than those in previous experiments. Loading rates, molasses lifetimes, magnetic-trapping times, and temperatures were measured using photoionization and electron detection.

J. Berrocal, E. Altozano, Francisco Domínguez +3 more

Two-ion crystals constitute a platform for investigations of quantum nature that can be extended to any ion \nspecies or charged particle provided one of the ions in the crystal can be directly laser cooled and manipulated \nwith laser radiation. This paper presents the formation of two-ion crystals for quantum metrology in a 7-tesla \nopen-ring Penning trap. 40Ca+ ions are produced either internally by photoionization or externally in a (Paul-trap) \nsource, transported through the strong magnetic field gradient of the superconducting solenoid, and captured \nin-flight with a mean kinetic energy of a few electronvolts with respect to the minimum of the Penning-trap \npotential well. Laser cooling of the two-ion crystal in a strong magnetic field towards reaching the quantum \nregime is also presented, with particular emphasis on the cooling of the radial modes.