FMR STUDIES OF MAGNETIC-ORDERING STRUCTURE IN FE CR SUPERLATTICES/

The FMR acoustic mode in parallel magnetic field orientation in 10-38 GHz frequency range at room temperature was studied for a series of mu ltilayer structures [Fe(11 Angstrom)/Cr(d)](12) with different thickne ss d of Cr spacer (5 Angstrom < d < 36 Angstrom). Expressions for acou stic and optic modes in parallel and perpendicular magnetic field orie ntation were obtained. The comparison of the experimental results with these formulas allowed to determine the magnetization dependence on t he magnetic held and to evaluate bilinear and biquadratic exchange cou pling for these samples. (C) 1998 Elsevier Science B.V. All rights res erved.