Chinese Physics B

Light-induced evaporative cooling in a magneto-optical trap

Hongyu Ma, Cheng Hua-Dong, Wang Yu-Zhu, Liang Liu

Published Nov 1, 2008• 3 citations

Abstract

This paper presents an experimental demonstration of light-induced evaporative cooling in a magneto-optical trap. An additional laser is used to interact with atoms at the edge of the atomic cloud in the trap. These atoms get an additional force and evaporated away from the trap by both the magnetic field and laser fields. The remaining atoms have lower kinetic energy and thus are cooled. It reports the measurements on the temperature and atomic number after the evaporative cooling with different parameters including the distance between the laser and the centre of the atomic cloud, the detuning, the intensity. The results show that the light-induced evaporative cooling is a way to generate an ultra-cold atom source.

DOI: 10.1088/1674-1056/17/11/037

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