Brillouin Light Scattering studies on ultra-thin ferromagnetic films

Brillouin Light Scattering (BLS) is a method to determine the frequencies , f , of the spin wave modes in even ultra thin (a few monolayers) magnetic films by determining the wavelength shift of inelastically scattered light from the magnetic surface using a tandem Fabry-Perot interferometer (f < 150 GHz).

The spin wave modes have frequencies dependent on e.g. the gyromagnetic ratio, surface and magnetocrystalline anisotropy strengths and as such provides a means of measuring these quantities, which otherwise is difficult especially for thin films.

A unique in-situ BLS facility, where the BLS instrument is integrated with a UHV deposition chamber in which the investigated sample is prepared, has been installed in the Thin Film Magnetism group at Cavendish, Univ. of Cambridge, UK. Being a magneto-optical method it renders itself well to be used in conjunction with the sample fabrication in the deposition chamber.

PhD work at Cavendish Lab Cambridge UK, group: S. McPhail, WS Lew, Dr M. Tselepi, Athens, TMR fellow, Dr Y. Xu, Shanghai, EPSRC, S Steinmüller, MPhil, F. Montaigne, Paris, academic staff, Univ. Nancy, France.

S. J. Steinmuller et al., "Spin dynamics in an ultrathin Fe film in the vicinity of the superparamagnetic/ferromagnetic phase transition," Physical Review B. Condensed Matter and Materials Physics, vol. 70, no. 2, s. 024420, 2004