Author/Authors :
Kutnyakhov، نويسنده , , D. and Lushchyk، نويسنده , , P. and Fognini، نويسنده , , A. and Perriard، نويسنده , , D. and Kolbe، نويسنده , , M. and Medjanik، نويسنده , , K. and Fedchenko، نويسنده , , E. and Nepijko، نويسنده , , S.A. and Elmers، نويسنده , , H.J. and Salvatella، نويسنده , , G. and Stieger، نويسنده , , C. and Gort، نويسنده , , R. and Bنhler، نويسنده , , T. and Michlmayer، نويسنده , , T. and Acremann، نويسنده , , Y. and Vat، نويسنده ,
Abstract :
As Stern–Gerlach type spin filters do not work with electrons, spin analysis of electron beams is accomplished by spin-dependent scattering processes based on spin–orbit or exchange interaction. Existing polarimeters are single-channel devices characterized by an inherently low figure of merit (FoM) of typically 10−4–10−3. This single-channel approach is not compatible with parallel imaging microscopes and also not with modern electron spectrometers that acquire a certain energy and angular interval simultaneously. We present a novel type of polarimeter that can transport a full image by making use of k-parallel conservation in low-energy electron diffraction. We studied specular reflection from Ir (001) because this spin-filter crystal provides a high analyzing power combined with a “lifetime” in UHV of a full day. One good working point is centered at 39 eV scattering energy with a broad maximum of 5 eV usable width. A second one at about 10 eV shows a narrower profile but much higher FoM. A relativistic layer-KKR SPLEED calculation shows good agreement with measurements.
Keywords :
Imaging spin filter , Ir (001) , Multichannel spin detection , Hemispherical electron energy analyzer
