Magnetic Spectroscopies

(MOKE and XMCD)

Understanding the interaction of light with magnetic materials has been a subject of intense investigations, because it is interesting both for an understanding of fundamental excitations, as well as for advancing data storage technologies. Fortunately, advances in high harmonic generation (HHG) extreme ultraviolet (EUV) light sources provide unique new capabilities for probing magnetic materials –

• The broad energy range of EUV HHG sources span the entire M-shell absorption edges of many magnetic materials, allowing the magnetic state to be read out simultaneously in multiple elements of alloys and multilayers
• EUV harmonics can be produced with linear and circular polarization, thus accessing MOKE and XMCD spectroscopies
• EUV harmonics are perfectly synchronized to the driving laser, with the ability to capture the fastest charge and spin dynamics
• Several experiments successfully used XUUS EUV sources to uncover how strong interactions influence dynamics in magnetic alloys, and identified the importance of exchange interactions, ultrafast superdiffusive spin currents, magnons, band mirroring and spin scattering in magnetic multilayers – in many cases occurring simultaneously