Dynamics of spintronic materials: Exploration in the time and frequency domain

X-ray and neutron reflectivity are mature experimental techniques for the exploration of film thicknesses and interface roughnesses on the nanoscale. Combining with photon and neutron polarization, these methods can be carried forward to the analysis of magnetic thin films and magnetic domain structures. New opportunities open up when these methods are used either in the time or in the frequency domain. Then dynamical processes can be studied such as domain oscillations, domain propagation, precession of spins, and damping effects. Two methods are discussed which have been developed recently: polarized neutron reflectivity from magnetic films in an alternating magnetic field and time resolved resonant magnetic x-ray reflectivity of the free precessional dynamics in films and multilayers