EMR Study of Electronic and Magnetic Ordering in Doped CaMn1-x,yMx,yO3 (M = Ru, Mo) Perovskites

A.I. Shamesa, M. Auslenderb, E. Rozenberga, G. Gorodetskya, C. Martinc and A. Maignanc aDepartment of Physics, Ben Gurion University of the Negev, P.O. Box 653, Be'er-Sheva 84105, Israel bDepartment of Electrical Engineering, Ben Gurion University of the Negev, P.O. Box 653, Be'er-Sheva 84105, Israel cLaboratoire CRISMAT, UMR 6508, ISMRA, 14050 Caen, Cedex, France

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Received: 24 04 2005;

X-band electron magnetic resonance measurements of polycrystalline CaMn1-x,yMx,yO3 (M = Ru, 0≤x≤0.5; M = Mo, 0≤y≤0.14) samples were performed at 120 K≤ T≤540 K. The observed anomalies of electron magnetic resonance parameters correlate pretty well with the temperatures of antiferro-, ferromagnetic-like, and orbital/charge-ordering transitions in these systems and specify phase diagrams obtained by other techniques. However, a strong difference between resonant properties of Ru- and Mo-doped series is observed in both paramagnetic and magnetically ordered states. To describe such a difference, the energy bands diagrams, which comprise the deep impurity t2g-like states + eg-like conductive band for CaMn1-xRuxO3 and shallow impurity states + conductive band, both having eg-like symmetry, for CaMn1-yMoyO3, are proposed. Specific electrons' contribution to the electron magnetic resonance line width explains concentration and temperature dependences of this parameter in the paramagnetic state in considered systems.

DOI: 10.12693/APhysPolA.108.235 PACS numbers:75.30.Kz, 75.47.Lx, 76.30.-v, 76.50.+g