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Large LFMR observed in twinned La2/3Ca1/3MnO3 thin films epitaxially grown on YSZ-buffered SOI substrates

J. Li·P. Wang·J. Y. Xiang·X. H. Zhu·W. Peng·Y. F. Chen·D. N. Zheng·Z. W. Li
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Abstract

La2/3Ca1/3MnO3 thin films have been grown on yttria-stabilized zirconia (YSZ) buffered silicon-on-insulator (SOI) substrate by the pulsed laser deposition technique. While full cube-on-cube epitaxy was achieved for the YSZ layer, the top manganite layer was multi-domain-oriented, with a coexistence of cube-on-cube and cube-on-diagonal epitaxy. Due to a combined influence from the magnetocrystalline anisotropy and the magnetoelastic anisotropy, in zero field the local spin orientation varies across the twin boundaries. As a result, a quite large low-field magnetoresistance (LFMR) based on spin-dependent tunnelling was observed. The film shows a resistance change of ~20% in a magnetic field <1000 Oe at 50 K, which is promising for real applications.

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J. Li, P. Wang, J. Y. Xiang, X. H. Zhu, W. Peng, Y. F. Chen, D. N. Zheng, Z. W. Li. 2004-07-02. Large LFMR observed in twinned La2/3Ca1/3MnO3 thin films epitaxially grown on YSZ-buffered SOI substrates. https://arxiv.org/abs/cond-mat/0407053

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