Distributed-feedback dye-doped solgel silica lasers

Dye-doped solgel silica lasers with distributed feedback were demonstrated. Solgel silica slabs doped with Rhodamine 6G or Coumarin 460 dyes were fabricated. Periodic gain modulation in dye-doped solgel silica slabs were created by the interference pattern of the pumped laser beams diffracted by a holographic grating. Laser pulse trains with subnanosecond spikes were induced. Laser emission wavelengths were centered at 480 and 585 nm for Rhodamine 6G and Coumarin 460, respectively. It was possible for us to tune approximately 20 nm around the emission centers by varying the intersection angle. The laser linewidth was of the order of 60 pm.