Controlling ferroelectric hysteresis offsets in PbTiO$_{3}$ based superlattices
Abstract
Ferroelectric materials are characterized by degenerate ground states with multiple polarization directions. In a ferroelectric capacitor this should manifest as equally favourable up and down polarization states. However, this ideal behavior is rarely observed in ferroelectric thin films and superlattice devices, which generally exhibit a built-in bias which favors one polarization state over the other. Often this polarization asymmetry can be attributed to the electrodes. In this study we examine bias in PbTiO-based ferroelectric superlattices that is not due to the electrodes, but rather to the nature of the defects that form at the interfaces during growth. Using a combination of experiments and first-principles simulations, we are able to explain the sign of the observed built-in bias and its evolution with composition. Our insights allow us to design devices with zero built-in bias by controlling the composition and periodicity of the superlattices.
Keywords
Cite
@article{arxiv.2011.06082,
title = {Controlling ferroelectric hysteresis offsets in PbTiO$_{3}$ based superlattices},
author = {Simon Divilov and Hsiang-Chun Hsing and Mohammed Humed Yusuf and Anna Gura and Joseph A. Garlow and Myung-Geun Han and Massimiliano Stengel and John Bonini and Premala Chandra and Karin M. Rabe and Marivi Fernandez Serra and Matthew Dawber},
journal= {arXiv preprint arXiv:2011.06082},
year = {2020}
}