Dramatic changes in the magnetic coupling mechanism for La-doped CaMnO3.

Phys Rev Lett

Instituto de Física "Gleb Wataghin," UNICAMP, 13083-970, Campinas-SP, Brazil.

Published: June 2001

The exchange interactions in polycrystalline samples of Ca1-xLaxMnO3 (0.00< or =x< or =0.05) are studied by means of Raman scattering and electron paramagnetic resonance. Dramatic reductions in the spin-phonon interactions and magnetic correlations are observed for La doping levels as small as approximately 2%-3%. These results show that the charge carriers play an important role in the overall exchange coupling in the electron-doped manganites, even at very low doping levels.

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http://dx.doi.org/10.1103/PhysRevLett.86.5385DOI Listing

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