We report the prediction and observation of supra-binary ferroelectricity in a ferroelectric nanowire (FNW) covered with a semi-cylindrical gate that provides an anisotropic electric field in the FNW. There are gate-voltage-driven transitions between four polarization phases in FNW's cross section, dubbed axial-up, axial-down, radial-in and radial-out. They are determined by the interplay between the topological depolarization energy and the free energy induced by an anisotropic external electric field, in clear distinction from the conventional film-based binary ferroelectricity. When the FNW is mounted on a biased graphene nanoribbon (GNR), these transitions induce exotic current-voltage hysteresis in the FNW-GNR transistor. Our discovery suggests new operating mechanisms of ferroelectric devices. In particular, it enables intrinsic multi-bit information manipulation in parallel to the binary manipulation employed in data storage devices.
@article{arxiv.1912.12821,
title = {Supra-Binary Ferroelectricity in a Nanowire},
author = {Wentao Xu and Lihua Wang and Yeongjun Lee and D. ChangMo Yang and Amir Hajibabaei and Cheolmin Park and Tae-Woo Lee and Kwang S. Kim},
journal= {arXiv preprint arXiv:1912.12821},
year = {2025}
}