Pressure-temperature phase diagram of charge ordering in Nd1/2Sr1/2MnO3
CNR-SPIN and Dipartimento di Fisica, Università di Roma La Sapienza - Roma, Italy, EU
2 Graduate School of Science and Technology, Kobe University - Hyogo, Japan
Accepted: 2 November 2010
We observe how the charge-ordering (CO) temperature TCO 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.
PACS: 71.30.+h – Metal-insulator transitions and other electronic transitions / 62.50.-p – High-pressure effects in solids and liquids / 78.30.-j – Infrared and Raman spectra
© EPLA, 2010