Multiferroicity in Ga-substituted LuFeO3: A first-principles study

We report a theoretical design of multiferroic Lu1-xGaxFeO3 based on density functional theory calculations. While bulk LuFeO3 stabilizes in a nonpolar Pnma structure, varying the concentration of Ga inside Lu1-xGaxFeO3 is predicted to result in the following structural transitions: Pnma (x = 0 - 0.29)-> P6(3)cm (x = 0.29 - 0.81)-> Pna2(1) (x = 0.81 - 1). The hexagonal P6(3)cm phase possesses both a finite polarization and weak ferromagnetic moment, while the Pna2(1) phase is ferroelectric and antiferromagnetic. Moreover, noncollinear magnetism (associated with spin-orbit coupling) is found to be critical for the stabilization of this P6(3)cm phase. Variation of the electronic properties, such as density of states and band gap, are also reported.

Automated summary

We report the theoretical design of a multiferroic material Lu1-xGaxFeO3 based on density functional theory calculations. By varying the concentration of Ga, different structural transitions and variations in electronic properties can be achieved, which show potential for various applications.