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arXiv · 1011.0665

Pressure-temperature phase diagram of charge ordering in Nd1/2Sr1/2MnO3

P. Maselli·D. Nicoletti·A. Nucara·F. M. Vitucci·A. Irizawa·K. Shoji·T. Nanba·P. Calvani
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Abstract

We observe how the charge-ordering (CO) temperature of Nd1/2Sr1/2MnO3 decreases with the external pressure p from 160 K at p = 0 down to 30 K at p ~ 4.5 GPa, by measuring the values p, T where the far-infrared spectral weight of the metallic phase is fully recovered. We thus determine the (p, T) phase diagram of CO in that manganite. We also find that the parameter d(lnTCO)/dp which describes this metallization from the CO phase is equal and opposite to the quantity d(lnTc)/dp which governs the metallization of the paramagnetic state at comparable Curie temperatures Tc, in similar manganites at half doping.

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P. Maselli, D. Nicoletti, A. Nucara, F. M. Vitucci, A. Irizawa, K. Shoji, T. Nanba, P. Calvani. 2010-11-02. Pressure-temperature phase diagram of charge ordering in Nd1/2Sr1/2MnO3. https://doi.org/10.1209/0295-5075%2F92%2F47001

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