Room-temperature multiferroic properties of Ni-doped PbTiO3 nanocrystals

Abstract

Functional oxide materials and their interfaces have attained fascinating physical properties persuaded by the interaction of lattice vibration, charge, orbital, and spin degrees of freedom. The control of the material structure at the atomic scale by precise growth conditions of these oxide interfaces opens a new pathway to control the associated properties in nanoelectronics and random-access memory devices. Herein, we investigated tetragonal Ni-doped lead titanate (PTO) nanocrystals' structural, electrical and magnetic control properties. The atomic-scale structural and elemental investigation reveals the polarizations interface and the spin orientation of atoms, with interfacial structural parameter information, and the Ti/Ni/O ion displacement shows polarization configuration. The electric and magnetic control measurements clearly show the picture of the ferromagnetic and ferroelectric loop for Ni-doped PTO, which was further confirmed by using first-principles density functional theory (DFT) calculations. The spin-lattice coupling interaction persuaded by magnetic ions in the ferroelectric host material has been observed to turn it into a multiferroic. This well-maintained structure of PTO, with the introduction of magnetic ions that couple multiferroic properties, makes the new route for future static and random memory devices.