Abstract
The pressure- and anion-dependent electronic structure of Eu (, 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 and electronic orbitals. Anion substitution () enhances competing exchange pathways through spin-polarized anion 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.
- Received 24 September 2008
DOI:https://doi.org/10.1103/PhysRevLett.102.057206
©2009 American Physical Society