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

Authors
Granado, E Moreno, NO Martinho, H Garcia, A Sanjurjo, JA Torriani, I Rettori, C Neumeier, JJ Oseroff, SB
Citation
E. Granado et al., Dramatic changes in the magnetic coupling mechanism for La-doped CaMnO3, PHYS REV L, 86(23), 2001, pp. 5385-5388
Citations number
30
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW LETTERS
ISSN journal
00319007 → ACNP
Volume
86
Issue
23
Year of publication
2001
Pages
5385 - 5388
Database
ISI
SICI code
0031-9007(20010604)86:23<5385:DCITMC>2.0.ZU;2-L
Abstract
The exchange interactions in polycrystalline samples of Ca1-xLaxMnO3 (0.00 less than or equal to x less than or equal to 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 similar to2%-3%. These results show that the c harge carriers play an important role in the overall exchange coupling in t he electron-doped manganites, even at very low doping levels.