Magnetic and magnetoresistive properties of La0.7-xPrxPb0.3MnO3 perovskite polycrystalline have been systematically studied. The substitution of La ions by Pr ions causes the structural change from rhombohedral to orthorhombic and the suppression of ferromagnetism. Ferromagnetic-paramagnetic and metal-insulator transitions are significantly affected by the Pr content x. The magnetic order due to Pr doping exhibits an incomplete magnetic saturation and varies from the ferromagnetic long-range order to short-range one. This fact is in good agreement with the decrease of the total exchange integral, corresponding to the increase of the B value in Bloch's T3/2 law. Moreover, the decrease of the metal-insulator (MI) transition temperature TP and the increase of the magnetoresistance ratio with Pr doping are observed. It is suggested that the canted spins of the Mn moments induced by the substitution of Pr ions for La sites play an important role in the magnetic and magnetoresistance effect.
|Number of pages||5|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Issue number||5 A|
|Publication status||Published - 2003 May 1|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)