A micro random laser of dye solution-filled tube system based on electrospun fibers

Random lasers (RLs) have good application prospects in speckle-free imaging, micro sensing and micro-nano photonic devices due to their properties such as cavityless, miniaturization and low-spatial coherence. The minimization, emission mechanism and lasing property control of RLs still need to be explored. In this paper, we present a novel micro RL system in a dye solution-filled tube, where the coherent random lasing action is facilitated by the integration of electrospun fibers and gold nanoparticles (Au NPs). The electrospun fibers serve as the scattering medium, while the Au NPs produce the local plasmon resonance effect. The interaction effect improves the photon scattering rate, makes the photons form a ring resonator in the system, and realizes the coherent RL in the tube system. The microtube RL has a very small size, a convenient preparation method and stable emission properties. It can withstand more than 2000 times pumping while maintaining a stable emission intensity. The electrospun fibers are stable and uniform in morphology, which makes it easy to achieve mass production of microtube RL. The speckle-free imaging experiment shows the RL has low spatial coherence, which indicates that it's a good choice for micro speckle-free imaging. This work provides a convenient way to realize micro coherent RLs by electrospun fibers and could pave a way for applications in photonic devices.