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 μJ cm⁻², which is even further decreased to ca. 5–10 μJ cm⁻² for the devices emitting in the 1^st diffraction order. Additionally this new formulation exhibits a considerably higher efficiency of ca. 3%, and a higher half‐life of more than 1 × 10⁵ 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.