TUNABLE DISTRIBUTED‐FEEDBACK DYE LASER

Efficient broadly tunable dye‐laser action with a narrow line output has been demonstrated with a mirrorless laser system using distributed feedback. The feedback was obtained from a spatial modulation of both gain and index of refraction, induced by pumping a liquid organic dye solution with fringes formed by the interference of two coherent light beams. The device was tunable over 640 A either by varying the angle between interfering pump beams or the refractive index of the dye solvent. Linewidths less than 0.01 A were measured and a peak power of 36 kW was observed.