Nanosize confinement induced enhancement of spontaneous polarization in a ferroelectric nanowire

TL;DR

This paper demonstrates through first-principles calculations that nanosize confinement can significantly enhance spontaneous polarization in ferroelectric nanowires, with potential implications for nanodevice applications.

Contribution

It reveals that surface curvature-induced tension can counteract depolarizing effects, leading to increased polarization in ferroelectric nanowires at the nanoscale.

Findings

Spontaneous polarization in PbTiO3 nanowires is 1.26 times higher than bulk.

Surface curvature induces tension that enhances polarization.

Nanosize confinement can be used to improve ferroelectric nanowire performance.

Abstract

We theoretically showed that the spontaneous polarization in ferroelectric (FE) nanowires (NWs) can be considerably enhanced due to the nanosize confinement by the first-principles calculations. The spontaneous polarization along the wire direction in a fully-relaxed PbTiO3 NW with 1.8 nm diameter is 1.26 times higher than that of bulk counterpart. The tension induced by NW surface curvature counteracts the near-surface depolarizing effect and meanwhile leads to the unusual enhancement of spontaneous polarization. These findings indicated that FE NWs can be promising in the applications of nanodevices.