Graphene Magnetoresistance Control by Photoferroelectric Substrate

Area of Science:

• Condensed Matter Physics and Materials Science
• Nanotechnology and 2D Materials

Background:

• Two-dimensional (2D) materials exhibit high sensitivity to charge, enabling electrical control.
• Functionalizing 2D materials for specific device properties remains a significant challenge.
• Photoferroelectric substrates offer potential for external control of 2D material properties.

Purpose of the Study:

• To investigate electrical and optical methods for modifying the magnetoresistance of chemical vapor deposition (CVD)-grown graphene.
• To explore the use of photoferroelectric substrates for controlling graphene's magnetic and electronic properties.
• To demonstrate the potential for on-demand, wireless control of 2D material-based devices.

Main Methods:

• Utilized a photoferroelectric substrate to electrostatically influence CVD-deposited graphene.
• Applied electrical polarization switching to alter graphene's magnetoresistance.
• Employed bandgap light illumination to induce photovoltaic effects and modify graphene properties.
• Investigated all-optical imprinting and recovery of magnetoresistance, alongside magnetic control of transconductance.

Main Results:

• Achieved a 67% modification of graphene magnetoresistance via electrical control through Fermi level shift and charge mobility changes.
• Demonstrated similar control using only bandgap light due to the substrate's photovoltaic effect.
• Reported successful all-optical imprinting and recovery of magnetoresistance, plus magnetic control of transconductance.

Conclusions:

• Photoferroelectric substrates enable effective electrical and optical control over the magnetoresistive response of 2D graphene.
• Findings extend photoferroelectric control to magnetic properties in 2D systems.
• This work advances wireless operation capabilities for 2D material-based sensors and field-effect transistors.