Ferroelastically protected polarization switching pathways to control electrical conductivity in strain-graded ferroelectric nanoplates

Abstract

Charged domain walls have rarely been observed in ferroelectric materials because of instability by large electrostatic energy. In this work, the authors have stabilized charged domain structures by ferroelastic clamping and manipulated resultant electric conductance in ferroelectric nanomaterials. Ferroelectric nanoplates subjected to compressive misfit strain at the bottom but less external stress on the sidewalls exhibit a radial-quadrant in-plane ferroelectric domain structure that is electrostatically unstable but emerges due to the flexoelectric effect associated with the misfit strain relaxation. They report that significant electronic conduction occurs near the edge of a ferroelectric nanoplate and the enhanced electronic conduction can be suppressed by 180${}^{\ensuremath{\circ}}$ polarization switching in a reversible way.