Graphene magnetoresistance control by photoferroelectric substrate

TL;DR

This study demonstrates electrical and optical methods to control graphene's magnetoresistance using a photoferroelectric substrate, enabling new functionalities for sensors and transistors.

Contribution

It introduces a fully optical and electrical approach to modulate graphene magnetoresistance via a photoferroelectric substrate, expanding control capabilities in 2D materials.

Findings

Electrical control modifies magnetoresistance by 67%.

Optical control via substrate photovoltaic effect is demonstrated.

All-optical imprinting and recovery of magnetoresistance is achieved.

Abstract

Ultralow dimensionality of 2D layers magnifies their sensitivity to adjacent charges enabling even postprocessing electric control of multifunctional structures. However, functionalizing 2D layers remains an important challenge for on-demand device property exploitation. Here we report that an electrical and even fully optical way to control and write modifications to the magnetoresistive response of CVD-deposited graphene is achievable through the electrostatics of the photoferroelectric substrate. For electrical control, the ferroelectric polarization switch modifies graphene magnetoresistance by 67% due to a Fermi level shift with related modification in charge mobility. A similar function is also attained entirely by the bandgap light due to the substrate photovoltaic effect. Moreover, an all-optical way to imprint and recover graphene magnetoresistance by light is reported as well as magnetic control of graphene transconductance. These findings extend photoferroelectric control in 2D structures to new a magnetic dimension and advance wireless operation for sensors and field-effect transistors.