Cooling atoms in an optical trap by selective parametric excitation

Abstract

A detailed study of the temperature of a sample of cold atoms in a one-dimensional (1D) lattice far-off resonance optical trap (FORT) was carried out. The anharmonicity of the potential was exploited to perform energy-selective excitation and removal of the atoms, resulting in either heating or cooling of the remaining trapped sample. An energy-selective removal of atoms was observed as a consequence of parametric excitation of anharmonic vibrational modes. In addition, it was shown that the energy selectivity can be exploited to cool the trapped sample.