Grain boundary structures in La{sub 2/3}Ca{sub 1/3}MnO{sub 3} thin films
As with many other oxide-based compounds that exhibit electronic behavior, structural defects have a strong influence on the electronic properties of the CMR manganites. In this work, the authors have studied the effect of grain boundaries on the transport properties and on the local orientation of magnetization. Thin films of the perovskite-related La{sub 2/3}Ca{sub 1/3}MnO{sub 3} compound were deposited onto bicrystal substrates using pulsed laser deposition. Transport measurements showed some enhancement of magnetoresistance across the grain boundary. The structure of the boundary was evaluated by electron microscopy. In contrast with the highly meandering boundaries typically observed in bicrystals of high temperature superconductors, the boundaries in these films are relatively straight and well defined. However, magneto-optical imaging showed that the local magnetization was oriented out of the plane at the grain boundary while it was oriented within the plane in the grains on either side. This coordinated reorientation of local magnetization near the grain boundary leads to enhanced magnetoresistance across the boundary in low fields.
- Research Organization:
- Argonne National Lab., IL (US)
- Sponsoring Organization:
- US Department of Energy (US)
- DOE Contract Number:
- W-31109-ENG-38
- OSTI ID:
- 750562
- Report Number(s):
- ANL/MSD/CP-100313; TRN: US0003337
- Resource Relation:
- Conference: 44th Annual Conference on Magnetism and Magnetic Materials, San Jose, CA (US), 11/15/1999--11/18/1999; Other Information: PBD: 26 Oct 1999
- Country of Publication:
- United States
- Language:
- English
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