A detailed study of the Brillouin scattering cross section from spin waves
has been carried out for Fe(110)/Cu(111)/Fe(110)/Si(111) heterostructures,
with thickness of the two Fe layers of 20 Angstrom and 60 Angstrom, and int
erlayer Cu thickness variable in the range 0-33 Angstrom. We found that for
thicknesses of the Cu spacer larger than 6 Angstrom, the Brillouin spectru
m consists of the acoustical and optical spin wave modes, whose frequency s
eparation depends on the Cu layer thickness. A good agreement between the c
alculated and the measured cross sections has been obtained. An explanation
of the Stokes/anti-Stokes asymmetry of the acoustical mode is given in ter
ms of interference effects between the contributions due to the two dynamic
magnetization components. (C) 2001 American Institute of Physics.