A self-assembled platform
Photographer: Illustration: Chalmers University of Technology | Denis Baranov and Yen Strandqvist
When two tiny gold flakes meet in a salty aqueous solution, an interaction arises that causes them to form a pair. They are both positively charged as the aqueous solution covers them with double layers of ions (red and blue). This causes a repelling electrostatic force, but, due to the simultaneous influence of something called the ‘Casimir effect’, an attracting force is also created, and a stable balance arises. The two nanoflakes orient themselves facing each other, with a cavity between them formed, and they remain stable in this arrangement, for weeks of observations. This cavity then functions as an optical resonator, a device which offers a tunable system for studying combinations of light and matter known as polaritons.
