| الملخص: | <p>The low-temperature electronic structure of the van der Waals ferromagnet CrSiTe3 has been investigated. This ferromagnetic semiconductor has a magnetic bulk transition temperature of 33 K, which can reach up to 80 K in single- and few-layer flakes. X-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) measurements, carried out at the Cr <em>L</em><sub>2,3</sub> and Te <em>M</em><sub>b</sub> edges on in vacuo cleaved single crystals, give strong evidence for hybridization-mediated super-exchange between the Cr atoms. The observed chemical shift in the XAS, as well as the comparison of the XMCD with the calculated Cr L<sub>2,3</sub> multiplet spectra, confirm a strongly covalent bond between the Cr <em>3d</em>(<em>e</em><sub>g</sub>) and Te 5<em>p</em> states. Application of the XMCD sum rules gives a non-vanishing orbital moment, supporting a partial occupation of the <em>e<sub>g</sub></em> states, apart from the <em>t</em><sub>2<em>g</em></sub>. Also, the presence of a non-zero XMCD signal at the Te Mb edge confirms a Te 5<em>p</em> spin polarization due to mixing with the Cr <em>e<sub>g</sub></em> bonding states. The results strongly suggest that superexchange, instead of the previously suggested single ion anisotropy, is responsible for the low-temperature ferromagnetic ordering of 2D materials such as CrSiTe<sub>3</sub> and CrGeTe<sub>3</sub>. This demonstrates the interplay between electron correlation and ferromagnetism in insulating two-dimensional materials.</p>
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