# Ferroelectric Domains and Evolution Dynamics in Twisted CuInP2S6 Bilayers

## TL;DR

This paper explores how twisting bilayers of a ferroelectric material can control polar domains, offering new insights for digital memory devices.

## Contribution

The study introduces a novel mechanism for manipulating ferroelectric domains via twist angles and interlayer coupling in CuInP2S6.

## Key findings

- Polar domains can be created and manipulated in twisted CuInP2S6 bilayers due to stacking-dependent coupling.
- Thermal stability and polarization lifetimes are sensitive to twist angles and temperature.
- External electric fields and strain can further manipulate domain behavior.

## Abstract

Polar domains and their manipulation—particularly the creation and dynamic control—have garnered significant attention, owing to their rich physics and promising applications in digital memory devices. In this work, using density functional theory (DFT) and deep learning molecular dynamics (DLMD) simulations, it is demonstrated that polar domains can be created and manipulated in twisted bilayers of ferroelectric CuInP2S6, as a result of interfacial ferroelectric (antiferroelectric) coupling in AA (AB) stacked region. Unlike the topological polar vortex and skyrmions observed in superlattices of (PbTiO3)n/(SrTiO3)n and sliding bilayers of BN and MoS2, the underlying mechanism of polar domain formation in this system arises from stacking‐dependent energy barriers for ferroelectric switching and variations in switching speeds under thermal perturbations. Notably, the thermal stability and polarization lifetimes are highly sensitive to twist angles and temperature, and can be further manipulated by external electric fields and strain. Through multi‐scale simulations, this study provides a novel approach to exploring how twist angles influence domain evolution and underscores the potential for controlling local polarization in ferroelectric materials via rotational manipulation.

A novel mechanism to control ferroelectric and antiferroelectric domains in bilayer twisted CIPS via Moiré superlattices and interlayer coupling. Combined DFT and MLMD simulations reveal the twist‐angle‐dependent domain evolution, offering mechanistic insights and design principles for controllable domain switching and programmable nano electronic devices based on low‐dimensional materials.