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Resonance Raman Spectroscopy of Extreme Nanowires and Other 1D Systems
Published on: April 28, 2016
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Radial Stark Effect in (In,Ga)N Nanowires.
Jonas Lähnemann1, Pierre Corfdir1, Felix Feix1
1Paul-Drude-Institut für Festkörperelektronik , Hausvogteiplatz 5-7, 10117 Berlin, Germany.
Nano Letters
|January 21, 2016
Summary
We investigated indium gallium nitride nanowires, finding that built-in electric fields cause significant shifts in their light emission. This radial Stark effect explains their broad absorption, making them promising for solar energy applications.
Area of Science:
- Materials Science
- Nanotechnology
- Semiconductor Physics
Background:
- Indium gallium nitride (InGaN) alloys are crucial for optoelectronic devices.
- Understanding luminescence in InGaN nanowires is key for advanced applications.
- Low-indium InGaN nanowires present unique optical properties due to their structure.
Purpose of the Study:
- To investigate the luminescence properties of unintentionally doped and Si-doped InGaN nanowires.
- To understand the influence of Fermi level pinning and radial electric fields on emission.
- To explore the potential of InGaN nanowires for solar energy harvesting.
Main Methods:
- Growth of InGaN nanowires by molecular beam epitaxy on Si substrates.
- Characterization using X-ray diffractometry and energy dispersive X-ray spectroscopy.
- Analysis of temperature-dependent photoluminescence to study emission characteristics.
Main Results:
- Observed emission bands at lower energies than expected, attributed to Fermi level pinning.
- Identified strong radial built-in electric fields in nanowire sidewalls.
- Demonstrated a significant Stark shift in emission due to the radial electric field and compositional fluctuations.
Conclusions:
- Fermi level pinning and radial electric fields significantly impact InGaN nanowire luminescence.
- The radial Stark effect contributes to the broadband absorption of InGaN nanowires.
- InGaN nanowires show promise as a platform for efficient solar energy applications.
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