Squeezing Light at the Nanoscale

June 19, 2018

These nanodiscs act as micro-resonators, trapping infrared photons and generating polaritons. When illuminated with infrared light, the discs concentrate light in a volume thousands of times smaller than is possible with standard optical materials, which can be used to detect single biomolecules. (Image courtesy of the Capasso Lab/Harvard SEAS)

Researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) [and the Department of Physics] have developed a new technique to squeeze infrared light into ultra-confined spaces, generating an intense, nanoscale antenna that could be used to detect single biomolecules.

The researchers harnessed the power of polaritons, particles that blur the distinction between light and matter. This ultra-confined light can be used to detect very small amounts of matter close to the polaritons. For example, many hazardous substances, such as formaldehyde, have an infrared signature that can be magnified by these antennas. The shape and size of the polaritons can also be tuned, paving the way to smart infrared detectors and biosensors. This work opens up a new frontier in nanophotonics.

The research is published in Science Advances...

Continue reading: "Squeezing light at the nanoscale Ultra-confined light could detect harmful molecules" by Leah Burrows, June 15, 2018. https://www.seas.harvard.edu/news/2018/06/squeezing-light-at-nanoscale.

Also read the research article: M. Tamagnone, A. Ambrosio, K. Chaudhary, L.A. Jauregui, P. Kim, W.L. Wilson, and F. Capasso, "Ultra-confined mid-infrared resonant phonon polaritons in van der Waals nanostructures," Science Advances 4 (2018) DOI: 10.1126/sciadv.aat7189.