Researchers in the group have created a 2-dimensional, surface plasmon analogue of Cherenkov radiation. By exciting a row of slits in a metal film with light at an oblique angle, the researchers were able to simulate a disturbance, essentially, a source of surface waves, which traveled faster than the phase velocity of surface plasmon polaritons on the interface between the metal and air. The resulting “Cherenkov” surface waves travel outward in wakes whose angle is determined by the ratio of the two velocities, easily tunable by changing the angle of incident light. This study has been published in Nature Nanotechnology, and can be found here.
- Surfing a Wake of Light — Harvard SEAS