Magnetization and resistivity in chromium doped manganites

Abstract

We report measurements of the magnetic and electrical properties of sintered manganites of the form La0.7Ca0.3CrxMn(1-x)O-3. We find that the peak in the conductivity moves rapidly to lower temperatures as the chromium content is increased and is completely absent for x > 0.2. The Curie temperature, as determined by magnetization measurements, is much less strongly suppressed, disappearing at x similar to 0.7. We interpret this behaviour in terms of the very different effects of the chromium in lifting spin and orbital degeneracy.