Electron and hole doping of monolayer WSe2 induced by twisted ferroelectric hexagonal boron nitride

TL;DR

This study demonstrates that twisted ferroelectric hexagonal boron nitride can induce controllable electron and hole doping in monolayer WSe2, enabling new optoelectronic device functionalities.

Contribution

It reveals how ferroelectric hBN layers can imprint local doping in WSe2 and uses WSe2 as an optical probe for ferroelectricity in hBN.

Findings

Ferroelectric domains in twisted hBN induce local doping in WSe2.

Doping type and density are controllable by the relative position of WSe2.

The hBN/WSe2 heterostructure shows promise for optoelectronic applications.

Abstract

For the past few years, 2D ferroelectric materials have attracted strong interest for their potential in future nanoelectronics devices. The recent discovery of 2D ferroelectricity in twisted layers of insulating hexagonal boron nitride, one of the most used 2D materials, has opened the route to its integration into complex van der Waals heterostructures combining hybrid properties. Here we show that opposite polarizations in ferroelectric domains of a folded hBN layer can imprint local n and p doping in a semiconducting transition metal dichalcogenide WSe2 monolayer. We demonstrate that WSe2 can be used as an optical probe of ferroelectricity in hBN and show that the doping density and type can be controlled with the position of the semiconductor with respect to the ferroelectric interface. Our results establish the ferroelectric hBN/WSe2 van der Waals stacking as a promising optoelectronic structure.