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08:01
Fabrication of Zero Mode Waveguides for High Concentration Single Molecule Microscopy
Published on: May 12, 2020
High-order waveguide modes in ZnO nanowires
Tobias Voss1, Geoffry T Svacha, Eric Mazur
1Department of Physics and School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA.
Nano Letters
|November 21, 2007
Summary
Researchers studied light guiding in zinc oxide (ZnO) nanowires using tapered silica fibers. High-order modes were observed, with simulations confirming efficient light coupling and emission angles.
Area of Science:
- Optics
- Materials Science
- Nanotechnology
Background:
- Nanowires offer unique optical properties due to their size.
- Understanding light propagation in nanowires is crucial for photonic devices.
Purpose of the Study:
- To investigate the waveguiding properties of zinc oxide (ZnO) nanowires.
- To analyze the excitation of waveguide modes and light coupling efficiency.
Main Methods:
- Laser light injection into ZnO nanowires (approx. 250 nm diameter) using tapered silica fibers.
- Experimental observation of light propagation and emission.
- Numerical simulations to model waveguiding and coupling.
Main Results:
- High-order waveguide modes were frequently excited in ZnO nanowires.
- Significant light intensity was observed at the nanowire surface.
- Numerical simulations accurately reproduced experimental findings.
- A coupling efficiency of 50% between silica and ZnO nanowires was determined.
- An experimental emission angle of approximately 90 degrees was measured, matching simulations.
Conclusions:
- ZnO nanowires exhibit complex waveguiding behavior with surface-dominant modes.
- Tapered silica fibers are effective for exciting and studying modes in nanowires.
- Simulations provide a reliable tool for understanding light-matter interactions in ZnO nanowires.
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