title: Effects of asymmetric surface corrugations on fully metal-coated scanning near field optical microscopy tips.
abstract: We propose a new configuration for a fully metal coated scanning near field (SNOM) probe based on asymmetric corrugations in the metal coating. The variation in the metal surface induces coupling mechanisms leading to the creation of a localized hot spot under linearly polarized excitation. Field localization is an effect of paramount importance for resolution but cannot be achieved with standard axisymmetric fully metal-coated probes, unless a more cumbersome radially polarized excitation is used. Our simulations show that this promising structure allows one to simplify the mode injection procedures circumventing the need for a radially polarized beam.
authors.affiliation: EMPA, Swiss Federal Laboratories for Materials Testing and Research, Electronics/Metrology Laboratory, Ueberlandstrasse 129, CH-8600 Dübendorf, Switzerland. Valeria.Lotito@empa.ch
authors.forename: Valeria
authors.initials: V
authors.lastname: Lotito
authors.forename: Urs
authors.initials: U
authors.lastname: Sennhauser
authors.forename: Christian
authors.initials: C
authors.lastname: Hafner