Chinese Physics Letters

Polarization Gradient Cooling by Zeeman-Effect-Assisted Saturated Absorption

Shunli Han, Bing Cheng, Jingfang Zhang, Xu Yun-Fei, Wang Zhao-Ying, Qiang Lin

Published Dec 1, 2009• 3 citations

Abstract

A novel and simple method to realize polarization gradient cooling (PGC) is reported. The stabilizing, shifting and rapid tuning of the frequency of the external cavity diode laser is realized by using the Zeeman-effect-assisted Doppler-free saturated absorption technique. Based on this convenient technique, 87 Rb cold atoms are captured from room-temperature background vapor in the magneto-optical trap (MOT). Meanwhile, the steady-state number, the density and the lifetime of atoms in the MOT are measured. Subsequently, a frequency-fast-varying circuit is designed to realize PGC, which is demonstrated effectively and reliably in experiments. The temperature of the cold atom cloud is measured by two different methods, which coincide with each other.

DOI: 10.1088/0256-307x/26/12/123702

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