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Updated: Jan 9, 2026

Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Gate-Tunable Electroresistance in a Sliding Ferroelectric Tunnel Junction
Bozo Vareskic1, Finn G Kennedy2, Takashi Taniguchi3
1Department of Physics, Cornell University, Ithaca, New York 14853, United States.
Researchers created novel tunnel junctions using van der Waals ferroelectric barriers and graphene electrodes. These devices show tunable electroresistance, a property controllable by voltage, offering potential for new electronic applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Van der Waals heterostructures offer unique electronic properties.
- Ferroelectric materials provide tunable polarization.
- Graphene's unique electronic characteristics are suitable for advanced devices.
Purpose of the Study:
- To fabricate and characterize electrically gated tunnel junctions using a van der Waals ferroelectric barrier.
- To investigate the electroresistance effect in these novel devices.
- To understand the underlying physical mechanisms governing the observed behavior.
Main Methods:
- Fabrication of tunnel junctions with bilayer hexagonal boron nitride as the ferroelectric barrier and single-layer graphene as electrodes.
- Electrical measurements of electroresistance as a function of bias and gate voltage.
- Theoretical modeling incorporating quantum capacitance effects.
Main Results:
- Demonstrated substantial electroresistance tunable by reversing ferroelectric polarization.
- Observed that electroresistance magnitude and sign are controllable via bias and gate voltage.
- Validated a tunneling model considering graphene's quantum capacitance.
Conclusions:
- The fabricated devices exhibit significant, voltage-tunable tunneling electroresistance.
- The observed behavior is explained by a model considering electrode quantum capacitance.
- These findings open avenues for ferroelectric-tunable electronic devices.
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