Theory for measuring topology-based enhanced emission in a double-emitter system including plasmonic antennae

Hybrid plasmonic-photonic domains showcase remarkable non-Hermitian characteristics, offering unique benefits through their ability to exhibit gain and loss simultaneously. Here, in-depth analysis has been conducted on a multilayered structure that is enhanced by the presence of plasmonic antennae. These antennae are strategically placed to optimize the interaction with light, potentially improving the performance of the structure in various applications. The hybrid waveguide resonance mode, generated by combining the surface-plasmon polariton with waveguide modes and activated by the antenna modes, characterizes the multilayer. The antennae aid in hybridizing waveguide and surface-plasmon modes; in turn, the multilayer structure enhances near-field intensity and allows for tuning far-field responses through multiple resonances. The interaction between antennae is characterized by dark and bright modes, which can create bound states in the continuum because of destructive interference in radiation losses. The nonconservative nature of the open system enables exploration of non-Hermitian properties, complex topology, and exceptional points. Analytical, numerical, and experimental results enable the study of the system's behavior, and display that exceptional points significantly boost emission levels when measurements are taken in their vicinity. In conclusion, systems with hybrid architecture and including plasmonic antennae can provide enhanced sensitivity and demonstrate their potential value across a diverse array of applications. These include advanced sensing technologies and innovative communication systems, where the complete density matrix can be simplified, and non-Hermitian Hamiltonian frames can be utilized to explore entanglement dynamics and analyze systems much larger than feasible.