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Control of the colossal magnetoresistance by strain effect in Nd$_{0.5}$Ca$_{0.5}$MnO$_{3}$ thin films

E. Rauwel-Buzin·W. Prellier·Ch. Simon·S. Mercone·B. Mercey·B. Raveau·J. Sebek·J. Hejtmanek
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Abstract

Thin films of Nd$_{0.5}$Ca$_{0.5}$MnO$_{3}$ manganites with colossal magnetoresistance (CMR) properties have been synthesized by the Pulsed Laser Deposition technique on (100)-SrTiO$_{3}$. The lattice parameters of these manganites and correlatively their CMR properties can be controlled by the substrate temperature $T_{S}$. The maximum CMR effect at 75K, calculated as the ratio $ρ(H=0T)/ρ(H=7T)$ is 10$^4$ for a deposition temperature of $T_{S}=680$ degC. Structural studies show that the Nd$_{0.5}$Ca$_{0.5}$MnO$_{3}$ film is single phase, [010]-oriented and has a pseudocubic symmetry of the perovskite subcell with a=3.77$Å$ at room temperature. We suggest that correlation between lattice parameters, CMR and substrate temperature $T_{S}$ result mainly from substrate-induced strains which can weaken the charge-ordered state at low temperature.

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E. Rauwel-Buzin, W. Prellier, Ch. Simon, S. Mercone, B. Mercey, B. Raveau, J. Sebek, J. Hejtmanek. 2001-06-22. Control of the colossal magnetoresistance by strain effect in Nd$_{0.5}$Ca$_{0.5}$MnO$_{3}$ thin films. https://doi.org/10.1063/1.1390313

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