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Updated: Jul 12, 2025
11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
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Gaussian and Gaussian-pulsed-like Fermi velocity graphene structures
H García-Cervantes1, G J Escalera Santos2, F J García-Rodríguez3
1Tecnologías Emergentes Industriales e Informáticas, Universidad Tecnológica de León, Blvd. Universidad Tecnológica 225, San Carlos la Roncha, 37670 León, Guanajuato, Mexico.
Summary
Gaussian structures in graphene act as electron filters, enabling tunable band-pass filters and oscillating conductance. These structures offer control over electronic transport properties in monolayer graphene devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Gaussian and related structures offer versatile electronic transport modulation.
- Non-conventional profiles are explored for Fermi velocity barriers in graphene.
- Monolayer graphene's unique electronic properties are suitable for novel device applications.
Purpose of the Study:
- Investigate Gaussian Fermi velocity graphene barriers (G-FVGBs) as electron band-pass filters.
- Analyze Gaussian-pulsed-like Fermi velocity graphene superlattices (GPL-FVGSLs) for tunable conductance.
- Explore the transmission and transport properties of these novel graphene structures.
Main Methods:
- Theoretical study using the continuum model.
- Application of the transfer matrix method.
- Analysis via the Landauer-Büttiker formalism.
Main Results:
- G-FVGBs exhibit tunable, nearly flat transmission pass bands.
- Pass band quality improves with increased Fermi velocity ratio (ξmax), but range decreases.
- GPL-FVGSLs show high transmission regions that can form minibands and produce conductance oscillations.
- Conductance is largely independent of system size due to filtering saturation.
Conclusions:
- G-FVGBs and GPL-FVGSLs function as effective electron filters and tunable conductance devices.
- System parameters, including Fermi velocity ratio and superlattice configuration, allow for precise control.
- These findings open possibilities for advanced electronic devices based on engineered graphene structures.
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