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arXiv · 0706.0402

Sum-rules for electron energy-loss near-edge spectra

Ján Rusz·Olle Eriksson·Pavel Novák·Peter M. Oppeneer
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Abstract

We derive four sum-rule expressions for spectra measured in electron energy-loss near edge structure experiments. These sum-rules permit the determination spin and orbital magnetic moments, spin-orbit interaction and number of states, analogously to the sum rules of x-ray magnetic circular dichroism. The derivation of the sum-rules is based on dynamical electron diffraction theory and the properties of the mixed dynamic form-factor. The accuracy of the sum-rules is tested by a complete evaluation of the thickness dependent electron energy-loss spectra for iron, cobalt, and nickel crystals. We find that the sum-rules reproduce both spin and orbital moments with very good accuracy. Our results provide a foundation for the use of the energy loss magnetic chiral dichroism technique as a quantitative probe of element specific magnetic properties.

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Ján Rusz, Olle Eriksson, Pavel Novák, Peter M. Oppeneer. 2007-08-15. Sum-rules for electron energy-loss near-edge spectra. https://doi.org/10.1103/physrevb.76.060408

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