A dual-wavelength polymer random laser with the step-type cavity

Abstract A dual-wavelength random laser of polymer film is fabricated by a spincoating method, and the dual cavities of step type are prepared on a silica substrate. The random microstructure forms due to the phase separation in the fabrication process, and provides a multiscattering mechanism for random lasing. The wavelength of output emission alters from 450 nm to 467 nm, when the pump spot totally shifts from cavity A to Cavity B. The output intensities can be adjusted by the ratio of illuminate areas on the dual cavities. The design of step cavities provides simple approach of a dual-wavelength random lasing emission, demonstrating potentials for compact laser devices.