title: Field enhancement in apertureless near-field scanning optical microscopy.
abstract: The near field of an apertureless near-field scanning optical microscopy probe is investigated with a multiple-multipole technique to obtain optical fields in the vicinity of a silicon probe tip and a glass substrate. The results demonstrate that electric field enhancements of >15 relative to the incident fields can be achieved near a silicon tip, implying intensity enhancements of several orders of magnitude. This enhancement arises both from the antenna effect of the elongated probe and from a proximity effect when the probe is near the substrate surface and its image dipoles play a role.
authors.affiliation: JILA, National Institute of Standards and Technology, and University of Colorado, Boulder, Colorado 80309-0440, USA. bohn@murphy.colorado.edu
authors.forename: J L
authors.initials: JL
authors.lastname: Bohn
authors.forename: D J
authors.initials: DJ
authors.lastname: Nesbitt
authors.forename: A
authors.initials: A
authors.lastname: Gallagher