Seeing the Light - Bringing Plasmonic Nanofields Into Focus
A research team led by the Molecular Foundry's Jim Schuck demonstrated an innovative imaging concept to visualize plasmonic fields from devices with nanoscale resolution. In plasmonic devices, electromagnetic waves crowd into tiny metal structures, concentrating energy into nanoscale dimensions. This savvy coupling of electronics and photonics could be harnessed for high-speed data transmission or ultrafast detector arrays.
However, studying plasmonic fields in nanoscale devices presents a real roadblock for scientists, as examining these structures inherently alters their behavior. Previously, the team engineered bowtie-shaped plasmonic devices to steer light at the nanoscale. These nano-color sorter devices focus and sort light in tiny spaces to a desired set of colors or energies—crucial for detectors.
Now, by imaging fluorescence from gold within an bowtie and maximizing the number of photons collected, the team gleaned the position of plasmonic modes—oscillations of charge that result in optical resonance—just a few nanometers apart.
In parallel, the team developed a web-based toolkit designed to calculate images of plasmonic devices to simulate how changing the size and symmetry of a plasmonic antenna affects its optical properties. This toolkit is freely available for other researchers to download on http://www.nanohub.org, a computational resource for nanoscience and technology.