An Efficient and Color‐Tunable Solution‐Processed Organic Thin‐Film Laser with a Polymeric Top‐Layer Resonator

Thin film organic lasers represent attractive light sources for numerous applications. Currently, efforts are devoted to the development of low‐cost high‐performance and color‐tunable devices, whereby both the resonator and the active layer should consist of solution‐processable organic materials. Herein, solution‐processed distributed‐feedback lasers are reported with polymeric resonators on top of active films of perylene orange or carbon‐bridged oligo(p‐phenylenevinylene) dispersed in polystyrene, which combine these properties. These lasers emit in the 520–595 nm range and show low thresholds (≈1 kW cm⁻²) and long operational lifetimes (7 × 10⁵ pump pulses), which are comparable to other state‐of‐the‐art lasers that contain the same active materials but resonators made on inorganic substrates. Due to this top‐layer resonator configuration, the laser slope efficiencies of the present devices are remarkably superior. A centimeter‐size device emitting at different wavelengths within a broad spectral range, based on a perylene‐based film of uniform thickness that contributes to preserve a low threshold, is demonstrated.