Transport dynamics analysis in ferromagnetic heterojunction using Raman spectroscopy and magnetic force microscopy

• Main Authors: Ren Ren, Yijing Ren, Xuan Li, Liya Wen, Song Chen, Ziqiang Wu, Rongdong Xu
• Format: Article
• Language: English
• Published: Elsevier 2016-04-01
• Series: Progress in Natural Science: Materials International
• Subjects: Metal insulator transition (MIT); Strong correlated electrons; Positive magnetoresistance; Spin–orbital coupling; Spin–orbit dynamics
• Online Access: http://www.sciencedirect.com/science/article/pii/S1002007116300053

The ZnO/La0.7Sr0.3MnO3 thin film was epitaxially fabricated on LaAlO3 (100) by pulse laser deposition. The Raman scattering on the single layer LaSrMnO and junction ZnO/La0.7Sr0.3MnO3 was investigated in a giant softening by 490 cm−1 John-Teller, 620 and 703 cm−1 optical phonon modes. The Raman spectra LaSrMnO and ZnO/La0.7Sr0.3MnO3 were observed with distinct features, i.e., the thickness was in dependent of frequency and intensity. The dynamics results showed that the spin–orbital coupling was caused by anomalies tilt of MnO6 octahedron. The LSMO/ZnO junction exhibited excellent junction positive magneto-resistance behavior in the temperature range of 77–300 K. The kinetic energy gain was achieved by orbital competition, strong crystal field and charge order of energy band splitting. The transport orbits were in the environment of the ferromagnetic-orbital ordering. The structures of barriers could be adjusted by junction interface and domain boundary condition in terms of the presence of spin–orbital fluctuating.