2009/04/27 by Hamrle, Jaroslav, Gaier, Oksana, Trudel, Simon +3
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Other Condensed Matter (cond-mat.other)
paper · doi:10.48550/arxiv.0904.4194
We determine the spin wave exchange stiffness D and the exchange constant A for the full Heusler compound \CFS using Brillouin light scattering spectroscopy. We find an extraordinarily large value of D=715±20 meV Å2 (A=31.5±1.0 pJ/m) which is, to the best of our knowledge, only surpassed by the intermetallic compound Fe53Co47 (J. Appl. Phys. 75, 7021 (1994)). Furthermore, we provide a systematization of the exchange stiffnesses determined for a variety of Co2-based Heusler compounds. We find that for the investigated compounds, the exchange stiffness is a function of the valence electron concentration and the crystallographic ordering. The exchange stiffness increases when the valence electron concentration and/or the amount of the L21 ordering increase. A qualitative explanation for the dependence on the valence electron concentration is provided.