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Mapping the spin-dependent electron reflectivity of Fe and Co ferromagnetic thin films

J. Graf·C. Jozwiak·A. K. Schmid·Z. Hussain·A. Lanzara
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Abstract

Spin Polarized Low Energy Electron Microscopy is used as a spin dependent spectroscopic probe to study the spin dependent specular reflection of a polarized electron beam from two different magnetic thin film systems: Fe/W(110) and Co/W(110). The reflectivity and spin-dependent exchange-scattering asymmetry are studied as a function of electron kinetic energy and film thickness, as well as the time dependence. The largest value of the figure of merit for spin polarimetry is observed for a 5 monolayer thick film of Co/W(110) at an electron kinetic energy of 2eV. This value is 2 orders of magnitude higher than previously obtained with state of the art Mini-Mott polarimeter. We discuss implications of our results for the development of an electron-spin-polarimeter using the exchange-interaction at low energy.

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J. Graf, C. Jozwiak, A. K. Schmid, Z. Hussain, A. Lanzara. 2005-05-30. Mapping the spin-dependent electron reflectivity of Fe and Co ferromagnetic thin films. https://doi.org/10.1103/physrevb.71.144429

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