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Evaluating Plasmonic Transport in Current-carrying Silver Nanowires
Published on: December 11, 2013
Photocurrents in nanotube junctions.
D A Stewart1, François Léonard
1Sandia National Laboratories, Livermore, California 94551, USA.
Physical Review Letters
|September 28, 2004
Summary
Researchers calculated photocurrents in nanotube p-n junctions, revealing unique size effects and spectral peaks. These findings offer insights into nanoscale optoelectronic device performance.
Area of Science:
- Nanotechnology
- Quantum Physics
- Materials Science
Background:
- Nanotube p-n junctions are promising for nanoscale optoelectronic applications.
- Understanding photocurrent generation is crucial for device optimization.
Purpose of the Study:
- To calculate and analyze photocurrents in nanotube p-n junctions.
- To investigate the influence of device length and quantum effects on photocurrent.
Main Methods:
- Utilized a nonequilibrium Green function quantum transport formalism.
- Calculated short-circuit photocurrents in nanotube p-n junctions.
Main Results:
- Observed distinct photocurrent peaks across infrared, visible, and ultraviolet spectra.
- Identified unusual linear scaling and oscillations of photocurrent with device length.
- Linked oscillations to the valence band density of states.
Conclusions:
- Photocurrents exhibit complex behavior influenced by quantum effects and device dimensions.
- Size effects in nanoscale devices significantly impact photoresponse.
- Valence band density of states plays a key role in determining photoresponse magnitude and spectral characteristics.
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