Figure 4.

(a) Upper resonance (red squares) and lower resonance (blue circles) peak positions in the experimental extinction spectra of the hybrid core–shell Au@Ag nanorods and J-aggregates system, as a function of plasmon peak position in the spectrum of bare NRs and as a function of detuning δ. Red and blue solid curves show the theoretical UR and LR peak positions, respectively. The horizontal red dashed line indicates the spectral position of the J-band. The diagonal blue dashed line marks the position of the plasmon resonance of longitudinal modes of bare core–shell Au@Ag nanorods. (b) Schematic representation of strong coupling between J-aggregates exciton (left) and the NR plasmon (right) yielding two hybrid plexciton states.