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arXiv · 1107.0887

Itinerant and local magnetic moments in ferrimagnetic Mn2CoGa thin films probed by x-ray magnetic linear dichroism: experiment and ab initio theory

Markus Meinert·Jan-Michael Schmalhorst·Christoph Klewe·Günter Reiss·Elke Arenholz·Tim Böhnert·Kornelius Nielsch
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Abstract

Epitaxial thin films of the half-metallic Xa-compound Mn2CoGa (Hg2CuTi prototype) were prepared by dc magnetron co-sputtering with different heat treatments on MgO (001) substrates. High-quality films with a bulk magnetization of 1.95(5)\mu_B per unit cell were obtained. The L3,2 x-ray magnetic circular dichroism spectra agree with calculations based on density functional theory (DFT) and reveal the antiparallel alignment of the two inequivalent Mn moments. X-ray magnetic linear dichroism, in good agreement with theory as well, allows to distinguish between itinerant and local Mn moments. Based on non-collinear spin DFT it is shown that one of the two Mn moments has local character, whereas the other Mn moment and the Co moment are itinerant.

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Markus Meinert, Jan-Michael Schmalhorst, Christoph Klewe, Günter Reiss, Elke Arenholz, Tim Böhnert, Kornelius Nielsch. 2011-07-05. Itinerant and local magnetic moments in ferrimagnetic Mn2CoGa thin films probed by x-ray magnetic linear dichroism: experiment and ab initio theory. https://doi.org/10.1103/physrevb.84.132405

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