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Updated: May 27, 2026
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
The dynamical conductance of graphene tunnelling structures
Huan Zhang1, K S Chan, Zijing Lin
1Department of Physics and Materials Science, City University of Hong Kong, Hong Kong.
Nanotechnology
|November 24, 2011
Summary
Graphene tunneling structures exhibit unique capacitative dynamical conductance. Transmission resonances cause dips, unlike semiconductor nanostructures, with features varying by Fermi energy.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Graphene's unique electronic properties make it a candidate for advanced electronic devices.
- Understanding the dynamical conductance of graphene tunneling structures is crucial for device applications.
- Previous studies often focused on static conductance or simplified models.
Purpose of the Study:
- To numerically calculate the dynamical conductances of graphene tunneling structures.
- To investigate the role of interaction effects on conductance.
- To compare the behavior of graphene structures with traditional semiconductor nanostructures.
Main Methods:
- Scattering matrix method was employed for numerical calculations.
- Interaction effects were incorporated using a phenomenological approach.
- Dynamical conductance was analyzed across various Fermi energies and barrier configurations.
Main Results:
- The single-barrier graphene structure shows overall capacitative dynamical conductance.
- Transmission resonances in single-barrier structures lead to dips in the imaginary part of conductance.
- These dips differ from inductive peaks observed in semiconductor nanostructures.
- Dip sharpness is dependent on the Fermi energy relative to the barrier height.
- Double-barrier structures exhibit inductive behaviors due to inter-barrier resonances.
Conclusions:
- Graphene tunneling structures display distinct dynamical conductance characteristics compared to semiconductors.
- Fermi energy plays a critical role in shaping the resonance features.
- The study provides insights into the AC response of graphene-based electronic components.
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