Reentrant valence transition in EuO at high pressures: beyond the bond-valence model

Abstract

The pressure-dependent relation between Eu valence and lattice structure in model compound EuO is studied with synchrotron-based x-ray spectroscopic and diffraction techniques. Contrary to expectation, a 7% volume collapse at $\approx$ 45 GPa is accompanied by a reentrant Eu valence transition into a $\text{lower}$ valence state. In addition to highlighting the need for probing both structure and electronic states directly when valence information is sought in mixed-valent systems, the results also show that widely used bond-valence methods fail to quantitatively describe the complex electronic valence behavior of EuO under pressure.

5 pages, 4 figures

References in corpus (5)

• Quantum Criticality without Tuning in the Mixed Valence Compound beta-YbAlB4
• Strong valence fluctuation in the quantum critical heavy fermion superconductor beta-YbAlB4: A hard x-ray photoemission study
• Pressure-induced electronic mixing and enhancement of ferromagnetic ordering in EuX (X=Te, Se, S, O) magnetic semiconductors
• Simultaneous ferromagnetic metal-semiconductor transition in electron-doped EuO
• Quantum critical end point of the Kondo volume collapse

Cited by in corpus (4)

• Unified understanding of the valence transition in the rare-earth monochalcogenides under pressure
• Pressure induced amorphization and collapse of magnetic order in type-I clathrate Eu8Ga16Ge30
• The Rising Sun Envelope Method: an automatic and accurate peak location technique for XANES measurements
• Magnetic field induced modification of a first-order ferromagnetic transition in Eu2In