Numéro
J. Phys. IV France
Volume 07, Numéro C1, Mars 1997
7th INTERNATIONAL CONFERENCE ON FERRITES
Page(s) C1-621 - C1-624
DOI https://doi.org/10.1051/jp4:19971257
7th INTERNATIONAL CONFERENCE ON FERRITES

J. Phys. IV France 07 (1997) C1-621-C1-624

DOI: 10.1051/jp4:19971257

Recent trends in the Exploration of Colossal Magneto Resistance Manganites

B. Raveau, A. Maignan, V. Caignaert and Ch. Simon

Laboratoire CRISMAT, URA 1318 du CNRS, ISMRA et Université de Caen, 6 boulevard du Maréchal Juin, 14050 Caen cedex, France


Abstract
The recent developments of the colossal magnetoresistance (CMR) properties of the manganites Ln1-xAxMnO3 (A3 = Ca, Sr, Ba) are presented herein. Two types of oxides must be distinguished : type I oxides that display a FMM-PMI transition obtained for 0.2<x<0.5 and type II oxides x = 0.50 that exhibit an AFMI-FMM transition. Two key factors govern the CMR properties of these materials : the average size of the interpolated cations and the hole carrier density [Mn(III).Mn(IV) mixed valence]. The doping of the Mn sites by various cations M = Al, Ga, In, Sn, Ti, Mg, Fe is also studied showing spectacular results for magnesium and iron. The role of the structure is also discussed.



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