Effect of Mo doping for the Mn site in the ferromagnetic manganite La0.7Ca0.3MnO3

TL;DR

This study investigates how molybdenum doping at the manganese site affects the structural, electronic, and magnetic properties of La0.7Ca0.3MnO3, revealing increased resistivity, altered magnetic ordering, and enhanced magnetoresistance.

Contribution

It provides new insights into the effects of Mo doping on manganite properties, highlighting the role of induced Mn2+ ions and FM coupling mechanisms.

Findings

Resistivity and lattice parameters increase with Mo doping.

Long-range ferromagnetic order persists despite doping.

Magnetoresistance peaks at optimal doping level x=0.05.

Abstract

The structure, electronic, and magnetic properties of the Mo-doped perovskite La0.7Ca0.3Mn1-xMoxO3 (x < 0.1) have been studied. A significant increase in resistivity and lattice parameters were observed with Mo doping. A marginal decrease in the Curie temperature Tc and the associated metal-insulator transition Tp were observed. Magnetization data reveal that long-range ferromagnetic ordering persists in all samples studied and the saturation moment decreases linearly as x increases. Enhancement in magnetoresistance at near Tc in the Mo-doped compounds with an optimum doping value x = 0.05 was observed. The overall experimental results can be explained by considering the induced Mn2+ ions with Mo6+ in the Mo-doped systems, with the strong FM coupling between Mn4+/2+- O - Mn3+.