FLUCTUATIONS OF THE SPIN DENSITY IN METALLIC MAGNETS

Overview & Synopsis

The magnetism of transition metals in which the magnetic moment is carried by itinerant electrons is still a controversial topic. There is lack of agreement as to what kind of fluctuations are responsible for the ferromagnetic to paramagnetic transition, and even on the nature of the paramagnetic phase itself. Paramagnetic neutron scattering provides a powerful tool for probing magnetic fluctuations in the paramagnetic state and is sensitive to wave-vector dependent features which distinguish different current theories. We have exploited this sensitivity in studying the spin-spin correlation functions in metallic magnets using polarisation analysis to obtain a clean measurement of the paramagnetic cross-section.