Regulating Interfacial Spin Hall Conductivity with Ferroelectricity.

Abstract

We report a new physical phenomenon of active and enhanced control of the spin Hall conductivity (SHC) in a family of metal-ferroelectric multilayers. Rather than the direction of the built-in electric field, such ferroelectric regulation of SHC originates from the drastic change of the interfacial electronic state along with its intrinsic Berry phase near the Fermi level due to the distinct hybridization between the metal film and substrate when the ferroelectric polarization reverses. Using Pt/PbZrTiO3 multilayers as a representative model, we demonstrate the controllability of a large magnitude and even the sign of SHC in the Pt film at the two interfaces with an antitype conducting carrier in a ferroelectric substrate. The interfacial Rashba effect plays a role in contributing to the change of SHC through spin-projected band analysis. The present work makes a fundamental theoretical discovery and opens up a new direction to manipulate spin-charge conversion of thin-film layered structures by ferroelectricity, which is crucial for designing future electric and spintronic devices.