Dye-doped polymer microring laser coupled with stimulated resonant Raman scattering

Polymer ring laser was fabricated with 1,4-bis[2-[4-[N,N-di(p-totyl)amino]phenyl]vinyl]benzene (DADSB)-doped polyvinyl-pyrrolidone (PVP) thin films coated on an inner surface of a quartz microcapillary. Ring-waveguided multimode lasing was observed under pulsed optical pumping. With increasing excitation wavelengths, an additional emission peak based on stimulated resonant Raman scattering (SRRS) appeared with a Raman shift of the stretching vibration of DADSB. When the SRRS peak just overlapped with each ring laser modes, the emission intensity was periodically enhanced. Such a wavelength-selective Raman coupling can demonstrate a tunable single-mode microring laser.