title: Near-field amplitude and phase measurements using heterodyne optical feedback on solid-state lasers.
abstract: Heterodyne optical feedback on a solid-state laser is experimentally investigated as an efficient tool to characterize coherently near-field evanescent waves. A well-known topography of evanescent field is obtained via a total internal reflection of the light beam emitted by a class B Yb:Er glass laser. A subwavelength size optical fiber tip is scanned to locally probe the resulting evanescent wave in the near field. After a frequency shifting using a pair of acousto-optic modulators, the collected light is optically reinjected to excite the relaxation oscillations of the laser. The resulting dynamical response simultaneously allows very sensitive measurements of the amplitude and the phase of the evanescent wave. Extension of these preliminary results to near-field optical microscopy is suggested and discussed.
authors.affiliation: Centre Interdisciplinaire de Recherche Ions Lasers, Laser, Instrumentation Optique and Applications, 6 Boulevard Maréchal Juin, Caen 14050 Cedex, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Gilles
authors.forename: Sylvain
authors.initials: S
authors.lastname: Girard
authors.forename: Mathieu
authors.initials: M
authors.lastname: Laroche
authors.forename: Ali
authors.initials: A
authors.lastname: Belarouci