DOMAIN ANALYSIS IN EPITAXIAL IRON-ALUMINUM AND IRON-GOLD SANDWICHES WITH OSCILLATORY EXCHANGE

Epitaxially grown iron-iron sandwiches with wedge-shaped gold and alum inum interlayers are investigated by Kerr microscopy. While in the Fe- Au-Fe sample an oscillatory exchange interaction was confirmed which a ppears, however, of a rather weak and irregular nature, only one trans ition from ferromagnetic to 90-degrees-coupling was found in the Fe-Al -Fe sample. For Al thicknesses > 15 angstrom the domains assume an irr egular character indicating an essentially uncoupled nature. This find ing was confirmed by a new technique based on the magnetooptical Voigt effect observed at perpendicular incidence.