Vibration Assisted Polariton Wavefunction Evolution in Organic Nanofibers

Abstract

Formation of the composite photonic-excitonic particles, known as polaritons, is an emerging phenomenon in materials possessing strong coupling to light. The organic-based materials besides the strong light-matter interaction also demonstrate strong interaction of electronic and vibrational degrees of freedom. We utilize the Dirac-Frenkel variation principle to derive semiclassical equations for the vibration-assisted polariton wavefunction evolution when both types of interactions are treated as equally strong. By means of the approach, we study details of the polariton relaxation process and the mechanism of the polariton light emission. In particular, we propose the photon emission mechanism, which is realized when the polariton wave package exceeds the geometrical size of the nanosystem. To verify our conclusions we reproduce the fluorescence peak observed in experiment (Takazawa \textit{et.al.} Phys.Rev.Let. \textbf{105}:07401, 2010) and estimate the light-matter interaction parameter