Effects of lateral and substrate constraint on the piezoresponse of ferroelectric nanostructures

摘要

The effects of lateral constraint and substrate clamping on piezoresponse of ferroelectric materials at small scale are quantitatively evaluated in PbZr_(0.52)Ti_(0.48)O_3 nanotubes. Lateral clamping results in a reduction of the extrinsic contributions to the piezoresponse by almost an order of magnitude at low and intermediate fields. Similarly, at aspect ratios below 3:1 (height to width), constraint to the substrate leads to a drastic reduction of the extrinsic contributions to the piezoelectric response of the ferroelectric nanostructures. Both behaviors can be explained by an increased energy requirement for formation and motion of the ferroelastic non-180° domain walls in mechanically constrained systems.