Fig. 3: Motional narrowing for BIC-based exciton-polaritons.
From: Nonlinear polaritons in a monolayer semiconductor coupled to optical bound states in the continuum
a Spectral peak position, b linewidth as the full width at half maximum (FWHM), and c corresponding Q-factor for the PCS mode (black diamonds), lower polariton branch (LPB, blue circles), and upper polariton branch (UPB, red squares), extracted from fits and compared with the coupled harmonic oscillator model. Also shown are the parameters of the MoSe2 neutral exciton in the TM polarization (a, b green circles), the peak position of the uncoupled exciton in the TE polarization (a orange circles), and the estimated homogeneous linewidth of the excitons \(\gamma _{\mathrm{X}}^h\) (b black dashed line). The blue lines in b and c show the model calculations for the UPB FWHM and Q-factor
