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arXiv · 0712.3990

Supercooling and the Metal-Insulator Phase Transition of NdNiO$_{3}$

Abstract

We report the temperature and time dependence of electrical resistivity on high temperature, high oxygen pressure prepared polycrystalline samples of NdNiO_3. NdNiO_3 is metallic above 195 K and below that temperature it undergoes a transition to an insulating state. We find that on cooling NdNiO_3 below 195 K it goes into a state which is not in thermodynamic equilibrium and slowly relaxes over several hours. As we cool it further and go below about 110 K it goes into a stable insulating state. On heating the system from the insulating state towards 200 K we find that it remains stable and insulating and undergoes a rather sharp insulator to metal transition in the temperature range 185 K to 195 K. We try to make sense of these and a few other interesting observations on the basis of our current understanding of first order phase transitions, supercooling, and metal-insulator transitions.

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Devendra Kumar, K. P. Rajeev, J. A. Alonso, M. J. Martinez-Lope. 2008-01-10. Supercooling and the Metal-Insulator Phase Transition of NdNiO$_{3}$. https://arxiv.org/abs/0712.3990

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