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Angle-dependent carrier transmission in graphene p-n junctions
1College of Nanoscale Science and Engineering, The State University of New York at Albany, Albany, New York 12203, United States. ssutar@albany.edu
Nano Letters
|August 10, 2012
Summary
Carrier transmission probability in graphene p-n junctions depends on the angle of incidence. Researchers observed a pronounced peak in junction resistance with increasing angle, consistent with theoretical predictions for exfoliated and CVD-grown graphene.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Graphene exhibits unique electronic properties, making it a promising material for electronic devices.
- Understanding carrier transport in graphene p-n junctions is crucial for device applications.
- The influence of geometric factors on electronic properties in 2D materials is an active area of research.
Purpose of the Study:
- To investigate the angle-dependent carrier transmission probability in graphene p-n junctions.
- To explore the effect of junction geometry on electrical resistance.
- To compare experimental findings with theoretical predictions.
Main Methods:
- Fabrication of graphene p-n junctions using electrostatic doping via buried gates.
- Patterning graphene channels to create junctions at various angles.
- Measurement of junction resistance as a function of angle.
- Utilizing both exfoliated and chemical vapor deposition (CVD)-grown graphene samples.
Main Results:
- A distinct peak in junction resistance was observed.
- The resistance peak became more pronounced as the angle increased.
- This angular dependence was consistently observed across different graphene growth methods.
- Experimental results align with theoretical models of angle-dependent transmission probability.
Conclusions:
- The angle of carrier incidence significantly impacts transmission probability in graphene p-n junctions.
- Junction geometry plays a critical role in the electrical characteristics of graphene devices.
- The findings validate theoretical predictions and offer insights for designing graphene-based electronic components.
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