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Hot-Carrier-Mediated Photon Upconversion in Metal-Decorated Quantum Wells
Gururaj V Naik1, Alex J Welch1, Justin A Briggs1
1Materials Science and Engineering, Stanford University , 496 Lomita Mall, Stanford, California 94305, United States.
Nano Letters
|June 30, 2017
Summary
Researchers developed a novel photon upconversion method using hot carriers in plasmonic nanostructures. This technique converts lower-energy photons to higher-energy photons, with potential applications in bioimaging and photovoltaics.
Area of Science:
- Optoelectronics
- Materials Science
- Nanotechnology
Background:
- Photon upconversion is crucial for advanced technologies but remains challenging.
- Existing methods for frequency conversion are limited, especially for upconversion.
Purpose of the Study:
- To demonstrate a new photon upconversion technique using hot carriers in plasmonic nanostructures.
- To explore the potential of this method for practical applications.
Main Methods:
- Generated hot carriers (holes and electrons) via plasmon decay in illuminated metal nanoparticles (gold and silver).
- Injected hot carriers into adjacent GaN/InGaN semiconductor quantum wells.
- Observed radiative recombination to emit higher-energy photons.
Main Results:
- Achieved photon upconversion from 2.4 to 2.8 eV using GaN/InGaN quantum wells with plasmonic nanoparticles.
- Demonstrated linear scaling of upconversion efficiency with illumination power.
- Showcased tunability of the upconversion process based on nanoparticle geometry and light polarization.
Conclusions:
- Plasmonic nanostructures can effectively mediate photon upconversion through hot carrier injection.
- This technique offers a promising route for efficient wavelength conversion and energy applications.
- Potential impacts include advancements in bioimaging, on-chip optical devices, and solar energy harvesting.
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