Anomalous Hall effect in Gd-doped La{sub 2/3}Ca{sub 1/3}MnO{sub 3}
- Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)
Ceramic samples of composition (La{sub 1{minus}x}Gd{sub x}){sub 2/3}Ca{sub 1/3}MnO{sub 3} were prepared and used as targets to grow films onto LaAlO{sub 3} substrates by pulsed laser deposition. Comparison of the electrical resistance and thermopower, measured vs temperature and applied magnetic fields, indicates transport dominated by positively charged small polarons in the high temperature paramagnetic state. Nonetheless, the Hall effect, measured in 0.5 {mu}m thick films of composition {ital x}=0 and {ital x}=0.25, has the sign that is normally ascribed to negatively charged free carriers. The magnitude of the Hall coefficient decreases exponentially with increasing temperature with an activation energy that differs from that of the resistivity. This behavior and its anomalous negative sign are interpreted to result from face-diagonal hopping of small polarons in the Mn sublattice. {copyright} {ital 1997 American Institute of Physics.}
- Research Organization:
- University of Illinois
- DOE Contract Number:
- FG02-91ER45439
- OSTI ID:
- 496538
- Report Number(s):
- CONF-961141--
- Journal Information:
- Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 8 Vol. 81; ISSN JAPIAU; ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
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