Free Access
Microsc. Microanal. Microstruct.
Volume 5, Number 4-6, August / October / December 1994
Page(s) 381 - 388
Microsc. Microanal. Microstruct. 5, 381-388 (1994)
DOI: 10.1051/mmm:0199400504-6038100

Near-field magneto-optical microscopy

Viatcheslav I. Safarov, Vladimir A. Kosobukin, Claudine Hermann, Georges Lampel et Jacques Peretti

Laboratoire de Physique de la Matière Condensée, Ecole Polytechnique, 91128 Palaiseau Cedex, France

A scanning tunneling optical microscope (STOM) operating in total reflexion condition with variable incident angle and polarization sensitive detection of the evanescent mode has been developed to study near-field magneto-optical properties of thin magnetic films. The sample is deposited on the external face of a prism and illuminated in total reflexion conditions with linearly polarized laser light. The evanescent mode close to the surface is detected with a tip-ending monomode optical fiber connected at its other end to a photomultiplier tube equipped with a light-polarization analyzer. The polarization sensitivity of the whole system, which was found to depend on the tip condition, was characterized on the bare prism with s- and p-polarized excitations. The magneto-optical effect in the evanescent mode is measured through a lock-in amplifier by modulating the external magnetic field produced by a coil surrounding the tip. With this set-up we have mainly studied a dielectric garnet film exhibiting perpendicular magnetization. The images, obtained on this sample by measuring the magneto-optical effect under very low amplitude of the external magnetic field modulation, show up submicronic details due to magnetic domain wall motion.

0779F - Near-field scanning optical microscopes.
7570 - Magnetic properties of thin films, surfaces, and interfaces.
7820L - Magnetooptical effects.

Key words
Optical microscopy -- Thin films -- Magnetic materials -- Magneto-optical effects -- Scanning probe microscopy -- Photon scanning tunneling microscopy -- Metrology -- Physics

© EDP Sciences 1994