Scanning magneto-optical lens for surface analysis

A. Pratt*, M. Jacka

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


We demonstrate the essential principles for performing a novel form of metastable-atom microscopy, namely focusing and scanning of a He 23S beam. A magneto-optical lens, in conjunction with time-varying magnetic field components, has been used to scan a beam of He 23S atoms across a sample surface in a manner analogous to other scanning probe techniques. The instrument developed is the first to apply methods in the laser manipulation of atoms specifically to the study of surfaces. With the lens in its current arrangement, a beam of He 23S atoms with an intensity of ∼6 × 1012 atoms s-1 cm-2 may be directed anywhere within a sample area of ∼64 mm2 at a focal distance of 1.4 m and with a focal spot full-width at half-maximum of <2 mm. Such control over the intensity and position of the He 23S beam greatly benefits the surface analysis technique of metastable de-excitation spectroscopy, as demonstrated with example spectra from a clean Si(1 1 1) 7 × 7 surface.

Original languageEnglish
Article number055308
JournalJournal of Physics D: Applied Physics
Issue number5
Publication statusPublished - 9 Apr 2009

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