Control of up-to-down/down-to-up light-induced ferroelectric polarization reversal. Issue 9 (15th August 2022) - Tan, Huan
Abstract : Control of the final state of polarization switched by illumination is achieved in BaTiO3 films by the manipulation of the internal electric fields by using suitable bottom electrodes. Abstract : Light control of ferroelectric polarization is of interest for the exploitation of ferroelectric thin films in ultrafast data storage and logic functionalities. The rapidly oscillating electric field of light absorbed in a ferroelectric layer can suppress its polarization but cannot selectively reverse its direction. Here we take advantage of the built-in asymmetry at ferroelectric/electrode interfaces to break the up/down symmetry in uniaxial ferroelectrics to promote polarization reversal under illumination. It is shown that appropriate ferroelectric/metal structures allow the direction of the imprint electric field to be selected, which is instrumental for polarization reversal. This ability is further exploited by demonstrating the optical control of the resistance states in a ferroelectric capacitor.