Abstract
We demonstrate confinement of atoms in a dark, toroidal optical trap. We use a spatial light modulator to convert a single blue-detuned Gaussian laser beam to a superposition of Laguerre-Gaussian modes that forms a ring-shaped intensity null bounded harmonically in all directions. We measure a spin-relaxation lifetime of for a trap detuning of . For smaller detunings, a time-dependent relaxation rate is observed. We use these relaxation rate measurements and imaging diagnostics to optimize trap alignment in a programmable manner with the modulator. The results are compared with numerical simulations.
- Received 17 October 2007
DOI:https://doi.org/10.1103/PhysRevA.76.061404