| The bilayer manganite film La2-2xSr1+2xMn207(X = 0.32) were successfully prepared by pulsed laser deposition (PLD) method. By controlling the parameters of deposition, fabricated films are single phase and grown well on two kinds of substrates with different lattice constants. After transport property measurements, it is found that there is 80K deference between the two cusp temperatures in resistivity-temperature curves (TM-I) of the two films grown on SrTiO (001} and NdGaO (110). At the same time, the resistivity of the film on SrTiO (001} is 50 times higher than that of the film on NdGaO (110). We studied the influence of the interface strain and it shows that the lattice mismatch between substrate and film is the main reason of the above observations. Expand strain decreases TM-I with increasing resistivity and compressed strain has the opposite effect. Using Double Exchange model of Zener these results can be explained qualitatively.
|
PDF Full Text Request