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Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)

Measurement of loading and loss rates in a magneto-optical trap by direct event counting with atom number feedback

Youngwoon Choi, Seokchan Yoon, Sungsam Kang, Wookrae Kim, Jai-Hyung Lee, Kyungwon An

Published Aug 1, 2007• 0 citations
Publisher

Abstract

By using direct event-counting with atom-number feedback we investigated the loading rate of a magneto-optical trap as a function of the magnetic field gradient. We also studied the one- and two-atom loss rates as functions of trap laser intensity. All measurements were performed with a precisely prepared initial number of atoms.
DOI
10.1109/cleopr.2007.4391666

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We present a detailed analysis of the cold collision measurements performed in a high-gradient magneto-optical trap with a few trapped Cs atoms first presented in Ueberholz et al ( J. Phys. B: At. Mol. Opt. Phys. 33 (2000) L135 ). The ability to observe individual loss events allows us to identify two-body collisions that lead to the escape of only one of the colliding atoms (up to 10% of all collisional losses). Possible origins of these events are discussed here. We also observed strong modifications of the total loss rate with variations in the repumping laser intensity. This is explained by a simple semiclassical model based on optical suppression of hyperfine-changing collisions between ground-state atoms.
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