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.