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Observation of insulator-metal transition in EuNiO$_{3}$ under high pressure

R. Lengsdorf·A. Barla·J. A. Alonso·M. J. Martinez-Lope·H. Micklitz·M. M. Abd-Elmeguid
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Abstract

The charge transfer antiferromagnetic (T$_{N}$ =220 K) insulator EuNiO$_{3}$ undergoes, at ambient pressure, a temperature-induced metal insulator MI transition at T$_{MI}$=463 K. We have investigated the effect of pressure (up to p~20 GPa) on the electronic, magnetic and structural properties of EuNiO$_{3}$ using electrical resistance measurements, ${151}^$Eu nuclear resonance scattering of synchrotron radiation and x-ray diffraction, respectively. With increasing pressure we find at p$_{c}$ =5.8 GPa a transition from the insulating state to a metallic state, while the orthorhombic structure remains unchanged up to 20 GPa. The results are explained in terms of a gradual increase of the electronic bandwidth with increasing pressure, which results in a closing of the charge transfer gap. It is further shown that the pressure-induced metallic state exhibits magnetic order with a lowervalue of T$_{N}$ (T$_{N}$ ~120 K at 9.4 GPa) which disappears between 9.4 and 14.4 GPa.

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R. Lengsdorf, A. Barla, J. A. Alonso, M. J. Martinez-Lope, H. Micklitz, M. M. Abd-Elmeguid. 2005-04-12. Observation of insulator-metal transition in EuNiO$_{3}$ under high pressure. https://doi.org/10.1088/0953-8984%2F16%2F20%2F006

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