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Sum rules for X-ray magnetic circular dichroism spectra in strongly correlated ferromagnets

V. Yu. Irkhin·M. I. Katsnelson
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Abstract

It is proven that the sum rules for X-ray magnetic dichroism (XMCD) spectra that are used to separate spin and orbital contributions to the magnetic moment are formally correct for an arbitrary strength of electron-electron interactions. However, their practical application for strongly correlated systems can become complicated due to the spectral density weight spreading over a broad energy interval. Relevance of incoherent spectral density for the XMCD sum rules is illustrated by a simple model of a ferromagnet with orbital degrees of freedom.

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V. Yu. Irkhin, M. I. Katsnelson. 2005-07-05. Sum rules for X-ray magnetic circular dichroism spectra in strongly correlated ferromagnets. https://doi.org/10.1140/epjb%2Fe2005-00157-8

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