NEW POSSIBILITIES OF POLARIZED NEUTRON REFLECTOMETRY IN THE STUDY OF DOMAIN-STRUCTURE OF THIN MAGNETIC-FILMS

It has been shown that the use of neutron reflection from magnetically non-collinear media allows to determine the local (averaged over the region coherently illuminated by the neutron) and the mean magnetic in duction, the mean square direction cosines of the local magnetic induc tion of thin (similar to 10-500 nm) films. Thus, polarised neutron ref lectometry (PNR) can be used to study magnetic properties of such film s, when the use of the transmission depolarisation technique is proble matic. The first two Fourier transform coefficients of the angular dis tribution function of the domain magnetisation can be found in zero fi eld. Small-angle scattering at domains under reflection has been used to evaluate the mean domain size. The study of magnetisation processes in a Fe36Co64 (170 +/- 3 nm) film has been undertaken to demonstrate the new possibilities of PNR. Rotation of the polarisation vector unde r neutron reflection has been observed.