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Instability of metal-insulator transition against thermal cycling in phase separated Cr-doped manganites

R. Mahendiran·B. Raveau·M. Hervieu·C. Michel·A. Maignan
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Abstract

We show that metal-insulator transition in Pr0.5Ca0.5Mn1-xCrxO3 (x = 0.015-0.025) is unstable against thermal cycling. Insulator-metal transition shifts down and low temperature resistivity increases each time when the sample is cycled between a starting temperature TS and a final temperature TF. The effect is dramatic lower is x. Insulator-metal transition in x = 0.015 can be completely destroyed by thermal cycling in absence of magnetic field as well as under H = 2 T. Magnetic measurements suggest that ferromagnetic phase fraction decreases with thermal cycling. We suggest that increase in strains in ferromagnetic- charge ordered interface could be a possible origin of the observed effect.

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R. Mahendiran, B. Raveau, M. Hervieu, C. Michel, A. Maignan. 2001-07-26. Instability of metal-insulator transition against thermal cycling in phase separated Cr-doped manganites. https://doi.org/10.1103/physrevb.64.064424

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