Spin Polarization Measurements of Rare Earth Thin Films: a Study of Materials for Spintronic and Magnetoelectronic Devices

Spin polarization, the difference in the number of spin-up and spin-down electrons, is an intrinsic property of ferromagnetic materials. Materials with high spin polarization have important technological implications for magnetoâ¿"electronic devices, e. g. devices that use magnetic tunnel junctions (MTJ), giant magnetoresistance (GMR) and/or magnetic random access memory, (MRAM). The fundamental physics of high spin polarization materials forms the basis for future technological applications. In this work, measurements of spin polarization have been performed on câ¿"axis gadolinium and dysprosium thin films, epitaxially grown on (11-20) sapphire substrates with a tungsten (110) seed layer. The values of spin polarization of câ¿"axis epitaxial gadolinium and dysprosium films were obtained using the point contact Andreev reflection (PCAR) technique with quantitative analyses.