Review of Scientific Instruments

Detection of cold metastable atoms at a surface

Dominik Schneble, Masahiro Hasuo, T. Anker, Tilman Pfau, J. Mlynek

Published May 1, 2003• 5 citations

Abstract

A scheme for the detection of cold metastable atoms at surfaces with spatial and temporal resolution is studied experimentally, using methods of laser cooling and atom optics. Electron emission yields for deexcitation of the metastable states 1s5(J=2) and 1s3(J=0) of argon at a gold surface are compared with a technique that is based on optical pumping and the use of an evanescent-wave atom mirror as an internal-state filter, and are found to agree to within an uncertainty of 10%. The application of the detection scheme to time-of-flight spectroscopy of cold atom clouds is demonstrated. The detector has a field of view of 3 mm diameter, a spatial resolution of order 100 μm, and a time resolution of 20 μs, and the single-atom detection efficiency near the center of the field of view is 14% in the linear counting regime of up to 106 atoms/s.

DOI: 10.1063/1.1561597

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