Stable and Efficient Thin Layer DFB Lasers Based on Side-Chain Azobenzene Polymers

Using amorphous side-chain azobenzene-containing polymers, stable and efficient miniature lasers based on polarization gratings as distributed feedback are fabricated. The lasers with Rhodamine 700 dye as the emitter exhibit a low lasing threshold of ca. 20 mu J cm(-2), which is even further decreased to ca. 5-10 mu J cm(-2) for the devices emitting in the 1st diffraction order. Additionally this new formulation exhibits a considerably higher efficiency of ca. 3%, and a higher half-life of more than 1 x 10(5) shots. A wide wavelength tuning range of 115 nm is obtained for the same formulation only by changing grating frequency. A variation of polymer matrix, laser dye, and grating spatial frequency allows an extended tuning range between 611 and 873 nm.