Claydon, Jill S.6; Hassan, Sameh6; Damsgaard, Christian Danvad7; Hansen, Jørn Bindslev5; Jacobsen, Claus Schelde5; Xu, Yongbing B.6; van der Laan, Gerrit6
1 Magnetic Systems Group, LabChip Section, Department of Micro- and Nanotechnology, Technical University of Denmark2 LabChip Section, Department of Micro- and Nanotechnology, Technical University of Denmark3 Department of Micro- and Nanotechnology, Technical University of Denmark4 Quantum Physics and Information Techology, Department of Physics, Technical University of Denmark5 Department of Physics, Technical University of Denmark6 unknown7 Center for Electron Nanoscopy, Technical University of Denmark
We have used x-ray magnetic circular dichroism to study the element specific magnetic properties of ultrathin films of the Heusler alloy Co2MnGa at room temperature. Nine films were grown by molecular beam epitaxy on GaAs substrates and engineered to vary in stoichiometry as Co1.86Mn0.99Ga1, Co1.95Mn0.98Ga1, and Co1.97Mn0.96Ga1, with thicknesses of 5.3, 7.6, and 9.7 nm, and were capped with Al to prevent oxidization. Sum rule analysis revealed magnetic moments significantly lower than the values predicted theoretically, especially in the case of the Mn total magnetic moment. The results do not support the hypothesis that a large magnetic moment is transferred from Co to Mn, and may suggest that diffusion and reacted layers at ultrathin thicknesses can effect the establishment of a full Heusler structure.
Journal of Applied Physics, 2007, Vol 101, Issue 9