The thermoelectric power (TEP) and the electrical resistivity of the intergranular magnetoresistance composite (1-x)La_(2/3)Ca_(1/3)MnO_(3)/(x)yttria-stabilized zirconia (YSZ) (LCMO/YSZ) with x=0, 0.75, 1.25, 4.5, 13, 15, and 80 of YSZ have been measured from 300 down to 77 K. A pronounced TEP peak appears during phase transition for samples with x>0, while it is not observed for x=0. We suggest that this is due to the magnetic structure variation induced by lattice strain which is a result of the LCMO/YSZ boundary layers. The transition width in the temperature derived from dχ/dT, with χ the ac magnetic susceptibility, supports this interpretation.
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