Induced ferromagnetism and colossal magnetoresistance by Ir-doping in Pr1-xCaxMnO3
Laboratoire CRISMAT (UMR 6508 associée au CNRS) , ISMRA, 6 Boulevard du Maréchal Juin, 14050 Caen Cedex, France
Corresponding author: a email@example.com
Revised: 2 July 2001
Published online: 15 November 2001
The doping of the manganese site by iridium (up to 15% ) in the small A cation manganites PrCaxMnO3 (), has been investigated as a new method to suppress charge-ordering and induce CMR effects. Ir doping leads to ferromagnetism and to insulator to metal transitions, with high transition temperatures reaching 180 K and CMR ratio in 7 T as large as 104. The efficiency with which iridium induces ferromagnetism and CMR is compared to previous results obtained with other substitutions (Ru, Rh, Ni, Cr...). The ionic radius of the foreign cations and their mixed-valencies are found to be the main parameters governing the ability to collapse the charge-ordered state.
PACS: 71.30.+h – Metal-insulator transitions and other electronic transitions / 75.30.Vn – Colossal magnetoresistance / 75.25.+z – Spin arrangements in magnetically ordered materials (including neutron and spin-polarized electron studies, synchrotron-source x-ray scattering, etc.)
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2001