Optical detection of the sliding ferroelectric switching in hBN with a WSe2 monolayer

TL;DR

This paper demonstrates optical detection of ferroelectric switching in hexagonal boron nitride (hBN) using a WSe2 monolayer, enabling non-destructive, local probing of ferroelectric states with potential for memory device applications.

Contribution

It introduces a novel optical method to detect ferroelectric switching in hBN via coupling with a WSe2 monolayer, advancing non-invasive characterization techniques.

Findings

Successful optical detection of ferroelectric switching in hBN

Coupling between ferroelectric hBN and WSe2 enables local probing

Potential for applications in non-volatile memory devices

Abstract

When two BN layers are stacked in parallel in an AB or BA arrangement, a spontaneous out-of-plane electric polarization arises due to charge transfer in the out-of-plane B-N bonds. The ferroelectric switching from AB to BA (or BA to AB) can be achieved with a relatively small out-of-plane electric field through the in-plane sliding of one atomic layer over the other. However, the optical detection of such ferroelectric switching in hBN has not yet been demonstrated. In this study, we utilize an adjacent WSe2 monolayer to detect the ferroelectric switching in BN. This dynamic coupling between a 2D ferroelectric and a 2D semiconductor allows for the fundamental investigation of the ferroelectric material using a non-destructive, local optical probe, offering promising applications for compact and non-volatile memory devices.