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تسجيل مستخدم جديدMagnetic anisotropy and valence states in La$_2$Co$_{1-x}$Mn$_{1+x}$O$_6$ ($xapprox 0.23$) thin films studied by X-ray absorption spectroscopy techniques
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X-ray absorption spectroscopy was used to determine the valence state in La$_2$Co$_{1-x}$Mn$_{1+x}$O$_6$ ($xapprox 0.23$) 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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