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X-ray photoemission characterization of La_{0.67}(Ca_{x}Sr_{1-x})_{0.33}MnO_{3} films

P. R. Broussard·V. M. Browning·V. C. Cestone
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Abstract

The Curie temperature and x-ray photoemission spectra of thin films of La_{0.67}(Ca_{x}Sr_{1-x})_{0.33}MnO_{3} (LCSMO) have been studied as a function of the Ca/Sr ratio. The films were grown by off-axis cosputtering from individual targets of La_{0.67}Ca_{0.33}MnO_{3} (LCMO) and La_{0.67}Sr_{0.33}MnO_{3} (LSMO) onto (100) oriented NdGaO_{3} substrates. The films grow with a (100) orientation, with no other orientations observed by x-ray diffraction. For the alloy mixtures, the Curie temperature, T_C, varies slowly as the Ca/Sr is decreased, remaining $\approx$ 300 K, while for the LCMO and LSMO films T_C is 260 and 330 K, respectively. The Mn-O valence structure is composed of two dominant peaks, whose positions undergo a change as the Ca fraction is decreased. The core lines behave as linear combinations of lines from pure LCMO and LSMO.

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P. R. Broussard, V. M. Browning, V. C. Cestone. 1999-01-19. X-ray photoemission characterization of La_{0.67}(Ca_{x}Sr_{1-x})_{0.33}MnO_{3} films. https://doi.org/10.1063/1.369995

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