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Evaluating Plasmonic Transport in Current-carrying Silver Nanowires
Published on: December 11, 2013
Current path in light emitting diodes based on nanowire ensembles.
F Limbach1, C Hauswald, J Lähnemann
1Paul-Drude-Institut für Festkörperelektronik, Hausvogteiplatz 5-7, D-10117 Berlin, Germany.
Nanotechnology
|October 25, 2012
Summary
Fabricated indium gallium nitride/gallium nitride nanowire (In,Ga)N/GaN NWs form light-emitting diodes (LEDs). Inhomogeneity in current density across individual nanowires significantly impacts LED performance and electroluminescence.
Area of Science:
- Materials Science
- Nanotechnology
- Optoelectronics
Background:
- Indium Gallium Nitride/Gallium Nitride (In,Ga)N/GaN nanowires (NWs) are promising for optoelectronic devices.
- Self-induced growth modes offer potential for controlled nanowire fabrication.
Purpose of the Study:
- To fabricate and characterize light-emitting diodes (LEDs) using ensembles of free-standing (In,Ga)N/GaN nanowires.
- To investigate the factors governing the electroluminescence and optoelectronic properties of these nanowire-based LEDs.
Main Methods:
- Molecular beam epitaxy for nanowire growth on silicon substrates.
- Electron-beam-induced current analysis, cathodoluminescence, and biased μ-photoluminescence spectroscopy.
- Transmission electron microscopy and electrical measurements for comprehensive characterization.
Main Results:
- Electroluminescence is primarily determined by variations in current densities across individual nanowires in parallel operation.
- Nanowires exhibit N-polarity.
- Quantum confined Stark effect is observed in the (In,Ga)N quantum well states.
Conclusions:
- Current path inhomogeneity in the nanowire ensemble is a critical factor for LED performance.
- The observed N-polarity and quantum confined Stark effect provide insights into the fundamental properties of these nanowires.
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