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arXiv · 1704.06411

Magnetic anisotropy and valence states in La$_2$Co$_{1-x}$Mn$_{1+x}$O$_6$ ($x\approx 0.23$) thin films studied by X-ray absorption spectroscopy techniques

Laura López-Mir·Regina Galceran·Javier Herrero-Martín·Bernat Bozzo·José Cisneros-Fernández·Elisa V. Pannunzio Miner·Lluís Balcells·Benjamín Martínez·Carlos Frontera
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Abstract

X-ray absorption spectroscopy was used to determine the valence state in La$_2$Co$_{1-x}$Mn$_{1+x}$O$_6$ ($x\approx 0.23$) thin films. We found that in spite of the non-stoichiometry, Co is in a divalent state while Mn ions show a mixed valence state. The relation of this finding with the magnetic properties of the films is discussed. X-ray magnetic circular dichroism measurements prove that magnetic anisotropy originates from Co spin-orbit coupling and it is strain-dependent: a strong increase of the angular contribution to the magnetic moment is found when in-plane (out-of-plane) and cell parameters get expanded (compressed). This behavior is reproduced by first order perturbation theory calculations.

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Laura López-Mir, Regina Galceran, Javier Herrero-Martín, Bernat Bozzo, José Cisneros-Fernández, Elisa V. Pannunzio Miner, Lluís Balcells, Benjamín Martínez, Carlos Frontera. 2017-04-21. Magnetic anisotropy and valence states in La$_2$Co$_{1-x}$Mn$_{1+x}$O$_6$ ($x\approx 0.23$) thin films studied by X-ray absorption spectroscopy techniques. https://doi.org/10.1103/physrevb.95.224434

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