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arXiv · 0901.1388

Enhanced Ferromagnetic Ordering in GdBaCo$_{2}$O$_{5.5+δ}$ Films on SrTiO3 (001) Substrate

G. Y. Wang·X. Y. Zhou·R. K. Zheng·Y. M. Hu·H. L. W. Chan·Y. Wang
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Abstract

The authors investigated the structure and properties of GdBaCo$_{2}$O$_{5.5+δ}$ thin films epitaxially grown on SrTiO$_{3}$ (001) single crystal substrates. The thin films were found to have a notable remnant magnetization above room temperature, which is much higher than that observed in bulk material. Transmission electron microscopy and x-ray diffraction patterns reveal that phase separation occurs in these films, and the phase responsible for the enhanced ferromagnetic order is $a$-oriented. The enhanced ferromagnetic order is attributed to the enhanced orbital order of Co$^{3+}$ in CoO$_{5}$ pyramids, and the disappearance of ferromagnetic to antiferromagnetic transition is explained the stabilization of higher spin state of Co$^{3+}$ in CoO$_{6}$ octahedra.

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G. Y. Wang, X. Y. Zhou, R. K. Zheng, Y. M. Hu, H. L. W. Chan, Y. Wang. 2009-01-10. Enhanced Ferromagnetic Ordering in GdBaCo$_{2}$O$_{5.5+δ}$ Films on SrTiO3 (001) Substrate. https://arxiv.org/abs/0901.1388

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