Resistive switching in metal–ferroelectric–metal junctions

Abstract

The aim of this work is to investigate the electron transport through metal–ferroelectric–metal (MFM) junctions with ultrathin barriers in order to determine its dependence on the polarization state of the barrier. To that end, heteroepitaxial $\mathrm{Pt/Pb}({\mathrm{Zr}}_{\text{0.52}}{\mathrm{Ti}}_{\text{0.48}}){\mathrm{O}}_3/{\mathrm{SrRuO}}_3$ junctions have been fabricated on lattice-matched ${\mathrm{SrTiO}}_3$ substrates. The current–voltage $\mathrm{(I–V)}$ characteristics of the MFM junctions involving a few-nanometer-thick $\mathrm{Pb}({\mathrm{Zr}}_{\text{0.52}}{\mathrm{Ti}}_{\text{0.48}}){\mathrm{O}}_3$ barriers have been recorded at temperatures between 4.2 K and 300 K. Typical $\mathrm{I–V}$ curves exhibit reproducible switching events at well-defined electric fields. The mechanism of charge transport through ultrathin barriers and the origin of the observed resistive switching effect are discussed.