標題: Tunable complex magnetic states of epitaxial core-shell metal oxide nanocrystals fabricated by the phase decomposition method
作者: Chang, S. J.
Lam, T. N.
Yang, C. Y.
Chen, Y. L.
Chu, Y. H.
Chueh, Y. L.
Tseng, Y. C.
材料科學與工程學系
Department of Materials Science and Engineering
關鍵字: XMCD;switching field distribution;magnetic oxide
公開日期: 13-Jul-2016
摘要: We report on the successful fabrication of epitaxial-discrete CoxFe3-xO4/CoO magnetic nanostructures on a SrTiO3 substrate as well as the results of a thorough investigation of the magnetic cross-reactions of the two phases in the vicinity of the epitaxial junction. These nanostructures were originally prepared as Fe3O4-CoO core-shell structures through the phase decomposition of bismuth perovskite precursors by pulsed-laser deposition. An antiphase boundary emerged during the structural/electronic transition from the CoO core to the Co1-xFe2+XO4 shell; this then developed into a ferrimagnetic/antiferromagnetic interface. Uncompensated spins (UCS) arose from the CoxFe3-xO4/CoO interface as a result of strong ferrimagnetic-antiferromagnetic interactions. A notable exchange bias as well as a significant exchange enhancement was observed owing to the UCS, which had a locking effect because of the decoupling of the Co1-xFe2+XO4/CoO reversal from the antiphase boundary. Control of the precursor ratio allowed for the fine-tuning of the Co1-xFe2+XO4 phase and the associated locking behaviors. This, in turn, allowed the anisotropy and coercivity of the nanostructures to be manipulated. Thus, we were able to create and thoroughly understand a complex epitaxial configuration with tunable structural and magnetic properties. This study should open new opportunities with regard to current magnetic oxide technology, which requires novel methods for pursuing extremity of controllable properties over an atomic landscape.
URI: http://dx.doi.org/10.1088/0022-3727/49/27/275001
http://hdl.handle.net/11536/134138
ISSN: 0022-3727
DOI: 10.1088/0022-3727/49/27/275001
期刊: JOURNAL OF PHYSICS D-APPLIED PHYSICS
Volume: 49
Issue: 27
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