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arXiv · 0808.0865

Pressure-induced electronic mixing and enhancement of ferromagnetic ordering in EuX (X=Te, Se, S, O) magnetic semiconductors

Narcizo M. Souza-Neto·Daniel Haskel·Yuan-Chieh Tseng·Gerard Lapertot
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Abstract

The pressure- and anion-dependent electronic structure of EuX (X=Te, Se, S, O) monochalcogenides is probed with element- and orbital-specific X-ray absorption spectroscopy in a diamond anvil cell. An isotropic lattice contraction enhances the ferromagnetic ordering temperature by inducing mixing of Eu 4{\it f} and 5{\it d} electronic orbitals. Anion substitution (Te $\to$ O) enhances competing exchange pathways through spin-polarized anion {\it p} states, counteracting the effect of the concomitant lattice contraction. The results have strong implications for efforts aimed at enhancing FM exchange interactions in thin films through interfacial strain or chemical substitutions.

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Narcizo M. Souza-Neto, Daniel Haskel, Yuan-Chieh Tseng, Gerard Lapertot. 2008-12-19. Pressure-induced electronic mixing and enhancement of ferromagnetic ordering in EuX (X=Te, Se, S, O) magnetic semiconductors. https://doi.org/10.1103/physrevlett.102.057206

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