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arXiv · 1112.3393

Magnetic non-uniformity and thermal hysteresis of magnetism in a manganite thin film

Surendra Singh·M. R. Fitzsimmons·T. Lookman·J. D. Thompson·H. Jeen·A. Biswas·M. A. Roldan·M. Varela
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Abstract

We measured the chemical and magnetic depth profiles of a single crystalline (La$_{1-x}$Pr$_x$)$_{1-y}$Ca$_y$MnO$_{3-δ}$ (x = 0.52\pm0.05, y = 0.23\pm0.04, δ = 0.14\pm0.10) film grown on a NdGaO3 substrate using x-ray reflectometry, electron microscopy, electron energy-loss spectroscopy and polarized neutron reflectometry. Our data indicate that the film exhibits coexistence of different magnetic phases as a function of depth. The magnetic depth profile is correlated with a variation of chemical composition with depth. The thermal hysteresis of ferromagnetic order in the film suggests a first order ferromagnetic transition at low temperatures.

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Surendra Singh, M. R. Fitzsimmons, T. Lookman, J. D. Thompson, H. Jeen, A. Biswas, M. A. Roldan, M. Varela. 2011-12-14. Magnetic non-uniformity and thermal hysteresis of magnetism in a manganite thin film. https://doi.org/10.1103/physrevlett.108.077207

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