Hybrid-plasmonic platform with tuneable light-matter coupling in a 2D parameter space

We will develop an open plasmonic platform, where the light-matter interaction is dynamically tuneable in a two-dimensional parameter space, namely detuning and interaction strength, and in contrast to closed resonator designs at least one surface is accessible to the environment. We will exploit the platform to demonstrate its potential to:
(i) control charge and long-range excitonic energy transport,
(ii) steer photophysical and photochemical reactions in organic materials,
(iii) explore fundamental properties arising from the non-Hermiticity of the coupled open quantum system,
(iv) develop sensor applications.
Control over the detuning of interacting resonances ‒ namely the surface plasmon polaritons (SPP) of a metal grating and 2D transition metal dichalcogenide (TMDC) excitons ‒ is achieved via the angle of incidence of light, while the interaction strength is manipulated by application of a gate voltage such that the exciton-photon system is steered between week coupling (WC) and strong coupling (SC). By placing conjugated organic molecules on top of the platform, the coupling regime between SPPs and “organic” excitons is controlled via gating of the TMDC layer. The advantage of the three-fold coupled system is that the various coupling coefficients in the mixed coupling regime add up according to their Hopfield-coefficients and as a result may yield the SC regime where individual coupling would remain in the WC regime.