Improved metastable de-excitation spectrometer using laser-cooling techniques
- Department of Physics, University of York, Heslington, York, YO10 5DD (United Kingdom)
Details of a new approach for performing metastable de-excitation spectroscopy are given. A beam of metastable (2 {sup 3}S) helium atoms, produced in a hollow cathode dc discharge, is collimated and subsequently focused using Doppler cooling of the 2 {sup 3}S{sub 1}-2 {sup 3}P{sub 2} transition at 1083 nm, forming an intense probe of up to 1x10{sup 12} atoms s{sup -1} cm{sup -2}. The large distance (2.5 m) between source and sample means that the beam is relatively free of UV photons and 2 {sup 1}S metastable atoms, removing the need for quench lamps and chopper wheels. As well as providing a clean high intensity source, the well defined nature of the beam is a necessary step towards using more sophisticated laser-cooling techniques with the ultimate aim of producing a metastable helium microscope. MDS and UPS spectra from Si(111) are shown.
- OSTI ID:
- 20722187
- Journal Information:
- Review of Scientific Instruments, Vol. 76, Issue 5; Other Information: DOI: 10.1063/1.1896685; (c) 2005 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
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