Towards enhancing the magnetic properties by morphology control of ATiO(3) (A = Mn, Fe, Ni) multiferroic materials

Abstract: Magnetic materials are of great interest due to their widespread applications in various technologies. Precise control of different aspects of the morphology and magnetic properties is a key aspect in establishing their relationship with material shapes and sizes. In this work, the density functional theory (DFT) is applied to investigate the surface structure and magnetic properties of low-index (1 1 0), (1 0 1), (1 0 0), (0 0 1), (1 1 1), (0 1 2) surfaces of ATiO(3) (A = Mn, Fe, Ni) multiferroic materials. In particular, a theoretical approach, based on the Wulff construction and magnetization density (M) index, is applied to infer the relationship between the morphology and surface magnetism. The results indicate that the magnetic properties of ATiO(3) materials can be controlled by the presence of exposed surfaces. In particular, the (0 0 1) and (1 1 1) surfaces are found to be adequate to enhance the superficial magnetism. The underlying reasons behind such mechanism are discussed from the perspective of uncompensated spins and charge-transfer processes along the exposed surfaces. This investigation suggests that the morphology-oriented ATiO(3) materials are good candidates for superior multiferroic applications.

Author(s): Ribeiro, RAP; Lacerda, LHS; Longo, E; Andres, J; de Lazaro, SR

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

DOI: 10.1016/j.jmmm.2018.12.002