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arXiv · 1510.07808

Spin-resolved Fermi surface of the localized ferromagnetic Heusler compound Cu$_2$MnAl measured with spin-polarized positron annihilation

Josef A. Weber·Andreas Bauer·Peter Böni·Hubert Ceeh·Stephen B. Dugdale·David Ernsting·Wolfgang Kreuzpaintner·Michael Leitner·Christian Pfleiderer·Christoph Hugenschmidt
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Abstract

We determined the bulk electronic structure in the prototypical Heusler compound Cu$_2$MnAl by measuring the Angular Correlation of Annihilation Radiation (2D-ACAR) using spin-polarized positrons. To this end, a new algorithm for reconstructing 3D densities from projections is introduced that allows us to corroborate the excellent agreement between our electronic structure calculations and the experimental data. The contribution of each individual Fermi surface sheet to the magnetization was identified, and summed to a total spin magnetic moment of $3.6\,\pm\,0.5\,μ_B/\mathrm{f.u.}$.

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Josef A. Weber, Andreas Bauer, Peter Böni, Hubert Ceeh, Stephen B. Dugdale, David Ernsting, Wolfgang Kreuzpaintner, Michael Leitner, Christian Pfleiderer, Christoph Hugenschmidt. 2015-10-27. Spin-resolved Fermi surface of the localized ferromagnetic Heusler compound Cu$_2$MnAl measured with spin-polarized positron annihilation. https://doi.org/10.1103/physrevlett.115.206404

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