Research expeditions:

• Emission control using bright and dark plasmon modes in graphene nanostructures

Plasmon modes in a single graphene disc are known to provide high spontaneous emission enhancement for nearby quantum dots. We were interested in the question of whether we can address two regimes of far field spectra: 1) both the emitter as well as the plasmon radiate and 2) only the emitter radiates but not the plasmon.

To tackle this question, we formulated a semi-analytical solution for a pair of graphene discs, whereby emission and absorption properties of dark and bright plasmonic modes were studied, as a function of graphene doping. Furthermore, we employed an open quantum systems formalism to show that under certain conditions, both the dark and bright dipolar modes in this system can support vacuum Rabi splittings for the plasmon-emitter coupling (Optics Express, 22:6400, 2014). This work has potential applications in cloaking and superabsorption.