Publications Details
Anomalous Hall effect in Gd-doped La{sub 2/3}Ca{sub 1/3}MnO{sub 3}
Ceramic samples of (La{sub 1-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. Electrical resistance and thermopower, measured vs temperature and applied magnetic fields indicate transport dominated by positive small polarons in the high temperature paramagnetic state. The Hall effect was measured in 0.5 {mu}m thick films of composition x=0 and x=0.25. No evidence for extraordinary hall effect was found in the paramagnetic regime. Instead, the magnitude of the Hall coefficient decreases exponentially with temperature. This behavior and its anomalous negative sign are interpreted to result from face-diagonal hopping of small polarons in the Mn sublattice.