Fig. 2: Strong plasmon–exciton coupling.
From: Probing plexciton emission from 2D materials on gold nanotrenches
a Reflection spectra from bare gold nanotrenches (see top schematic) of varying width, normalized to the ones from flat susbtrates. The curves are vertically offset for clarity. b Reflection spectra of the WSe2–Au-nanotrench coupled system, following the same width order as in (a). c Wavelength dependence (vertical axis) of the UP (black dots/stars) and LP (red dots/stars) as a function of plasmon resonance wavelength (horizontal axis) identified in the uncovered nanotrench areas. The energy splitting at zero detuning is \(\approx 80\) meV. d Calculated dispersion diagram based on the x-resolved LDOS using the BEM (see SI for details), where the (normalized) maxima corresponding to the LP and UP branches are indicated by the blue and black squares. Fitting to a coupled-oscillator model (COM), renders a Rabi-like splitting of \(\Omega \approx 80\) meV in experiment (c) and \(\Omega \approx 86.6\) meV in the BEM calculations (see Supp. Sec. 5A).
