Ferroelectric switching of interfacial dipoles in $\alpha$-RuCl$_3$/graphene heterostructure

TL;DR

This paper reports the discovery of electrically switchable, non-volatile interfacial dipoles in a van der Waals heterostructure, driven by charge transfer and exhibiting ferroelectric-like behavior near 30 K, unaffected by magnetic fields.

Contribution

It introduces a novel mechanism for ferroelectric switching in heterostructures based on interfacial charge transfer without structural sliding or twisting.

Findings

Demonstrated stable ferroelectric-like hysteresis loops at ~30 K.

Showed negligible influence of magnetic fields on dipole switching.

Established a new route for electrically tunable ferroelectric phenomena in 2D heterostructures.

Abstract

We demonstrate electrically switchable, non-volatile dipoles in graphene/thin hBN/$\alpha$-RuCl$_3$ heterostructures, stabilized purely by interfacial charge transfer across an atomically thin dielectric barrier. This mechanism requires no sliding or twisting to explicitly break inversion symmetry and produces robust ferroelectric-like hysteresis loops that emerge prominently near 30~K. Systematic measurements under strong in-plane and out-of-plane magnetic fields reveal negligible effects on the hysteresis characteristics, confirming that the primary mechanism driving the dipole switching is electrostatic. Our findings establish a distinct and robust route to electrically tunable ferroelectric phenomena in van der Waals heterostructures, opening opportunities to explore the interplay between interfacial charge transfer and temperature-tuned barrier crossing of dipole states at the atomic scale.