GHz tuning of a planar dye laser with single dispersive element

A new scheme for tuning a planar waveguide dye laser is presented. Because of the high gain produced in the waveguide structure, a high-dispersion slit-grating arrangement can be used as a feedback element of the laser. Output energy of a few tens of mJ, which corresponded to the saturated output of the amplifier, was obtained within a 2-GHz bandwidth. A very stable and repeatable output frequency was observed. The device demonstrates that, as long as the waveguide overcomes gain and refractive index inhomogeneities, a much higher energy output can be expected from scaled-up devices.