Dual-mode waveguiding of Raman and luminescence signals in a crystalline organic microplate

We demonstrate dual-mode waveguiding of Raman and luminescence signals using pi-conjugated organic 1,4-bis(3,5-bis(trifluoromethyl) cyanostyryl-2,5-dibromobenzene (CN-TSDB) microplates with single-crystal structure. The output Raman and photoluminescence (PL) spectra through the CN-TSDB microplates were recorded as a function of propagation distance using a high-resolution laser confocal microscope (LCM). Under 633 nm Raman excitation, which is outside the optical absorption of the microplates, the characteristic Raman modes of C-Br, -CF3, and -C=C- aromatic stretching were clearly observed at the output points. The decay characteristics of the LCM Raman intensities were comparable to those of LCM PL intensities. The intermolecular pi-pi interaction of CN-TSDB has been enhanced by the attractive interaction between the CN group and Br atoms, which induces efficient polariton propagation and plays an important role in dual-mode waveguiding.