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11:42
Fabrication of Gate-tunable Graphene Devices for Scanning Tunneling Microscopy Studies with Coulomb Impurities
Published on: July 24, 2015
Gate-controlled guiding of electrons in graphene
J R Williams1, Tony Low, M S Lundstrom
1School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Nature Nanotechnology
|February 15, 2011
Summary
Researchers demonstrate fiber-optic guiding in graphene using both n-type and p-type carriers. This electronic analog of optical fiber guiding could enable new forms of reconfigurable wiring in high-speed electronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Ballistic semiconductor structures enable optics-like phenomena in electronics.
- Graphene's unique properties allow for n and p carrier types, creating electronic analogues of optical devices with tunable refractive indices.
Purpose of the Study:
- To demonstrate electronic fiber-optic guiding in graphene.
- To investigate bipolar p-n junction guiding and unipolar guiding via total internal reflection.
- To explore gate-controlled modulation of guiding efficiency.
Main Methods:
- Utilized gate-controlled carrier density in graphene to create p-n junctions.
- Investigated angle-selective transmission for bipolar guiding.
- Employed total internal reflection controlled by carrier density for unipolar guiding.
- Performed numerical simulations for comparison.
Main Results:
- Successfully demonstrated electronic fiber-optic guiding in graphene.
- Showcased bipolar and unipolar guiding mechanisms.
- Observed modulation of guiding efficiency through electrical gating.
- Identified interface roughness as a limiting factor for guiding performance.
Conclusions:
- Graphene's dual carrier types facilitate the creation of electronic fiber-optic guiding.
- Gate-controlled guiding efficiency offers potential for dynamic control.
- Development of these guiding techniques may lead to electrically reconfigurable wiring in high-mobility devices.
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