Orbital order and ferromagnetism in LaMnO3 doped with Ga

TL;DR

This study uses first-principles calculations to explore how gallium doping affects the magnetic, electronic, and structural properties of LaMnO3, revealing reduced Jahn-Teller effects, altered orbital order, and stabilized ferromagnetism.

Contribution

It provides new insights into the effects of Ga doping on LaMnO3's properties, especially its orbital order and magnetic phases, using first-principles methods.

Findings

Ga doping reduces Jahn-Teller distortion and bandgap.

Ga doping weakens antiferromagnetic order and favors ferromagnetism.

Insulating ferromagnetic phase stabilized at x=0.50.

Abstract

We study from first principles the magnetic, electronic, orbital and structural properties of the LaMnO3 doped with gallium replacing the Mn-site. The gallium doping reduces the Jahn-Teller effect, and consequently the bandgap. Surprisingly, the system does not go towards a metallic phase because of the Mn-bandwidth reduction. The Ga-doping tends to reduce the orbital order typical of bulk antiferromagnetic LaMnO3 and consequently weakens the antiferromagnetic phase. The Ga-doping favors the G-type orbital order and layered-ordered ferromagnetic perovskite at x=0.50, both effects contribute to the formation of the insulating ferromagnetic phase in LaMn1-xGaxO3.