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Updated: Dec 3, 2025
13:02
Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
10.0K
Optical confinement in the nanocoax: coupling to the fundamental TEM-like mode
Optics Express
|October 29, 2020
Summary
We developed a new method to create tiny metal-insulator-metal nanocoaxes for optical applications. These nanocoaxes transmit light below the diffraction limit using a special optical beam.
Area of Science:
- Nanophotonics and optical engineering
- Materials science and nanotechnology
Background:
- Nanoscale coaxial cables (nanocoaxes) show potential for optical confinement in visible and near-infrared spectra.
- Existing fabrication methods may limit the optical addressability and aspect ratio of nanocoaxes.
Purpose of the Study:
- To report a novel nanofabrication process for creating optically addressable, high aspect ratio metal-insulator-metal nanocoaxes.
- To demonstrate sub-diffraction-limited optical transmission through these nanocoaxes.
Main Methods:
- Utilized atomic layer deposition of Platinum (Pt) and Aluminum Oxide (Al2O3) to fabricate sub-micrometer diameter nanocoaxes.
- Employed a radially polarized optical vortex beam for excitation.
- Interrogated optical transmission using a polarimetric imager.
- Performed finite element method (FEM) numerical simulations to support experimental findings.
Main Results:
- Successfully fabricated high aspect ratio metal-insulator-metal nanocoaxes with sub-micrometer diameters.
- Observed sub-diffraction-limited optical transmission, indicating efficient light confinement.
- Confirmed the propagation of the fundamental, TEM-like mode.
- FEM simulations validated experimental results and modeled taper geometries from large volumes to nanoscopic apertures.
Conclusions:
- The novel nanofabrication process enables the creation of advanced nanocoaxes for optical applications.
- Sub-diffraction-limited optical transmission is achievable with these nanocoaxes using specific excitation.
- The findings have implications for nanoscale optical devices and light manipulation.
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