Magic-wavelength optical dipole trap of cesium and rubidium atoms

Abstract

Optical dipole traps (ODT) with far-off-resonance laser are important tools in more and more present cold-atom experiments, which allow confinement of laser-cooled atoms with a long storage time. Particularly, the magic wavelength ODT can cancel the position-dependent spatially inhomogeneous light shift of desired atomic transition, which is introduced by the ODT laser beam. Now it plays an important role in the state-insensitive quantum engineering and the atomic optical clock. To verify the magic wavelength or the magic wavelength combination for D₂ line transition of cesium (Cs) and rubidium (Rb) atoms, we calculated and analyzed the light shift of the ¹³³Cs 6S_1/2 - 6P_3/2 transition for a monochromatic ODT, and also the ⁸⁷Rb 5S_1/2 - 5P_3/2 transition for a dichromatic ODT with a laser frequency ratio of 2:1. Also a dichromatic magic-wavelength ODT laser system for 87Rb atoms is proposed and experimentally realized by employing the quasi-phase-matched frequency doubling technique with telecom laser and fiber amplifier.