熔融静电纺丝法制备单根聚合物微米纤维全可见光谱的放大自发发射特性研究

具有高能量转化效率的微纳尺度的激光光源的开发将极大地促进光电子系统的进一步集成。本文采用熔融静电纺丝方法成功制备了单根有机聚合物微米纤维，所制备的微米纤维表面光滑，成规范的圆柱形结构。我们通过在聚合物纤维中掺入不同的荧光染料，实现了在整个可见光范围内的光发射可调性。在光泵浦条件下，我们详细研究了单根聚合物微米纤维的放大自发发射特性，三种颜色的微米纤维均表现了较低的阈值和高增益的放大自发发射特性。采用时域有限差分法模拟微米纤维中的电场分布结果表明，纤维的柱状微结构有效地将光限制在圆柱体内，形成环形腔反馈，并沿着轴向传播，因而发射光表现了很好的方向性。这种可见光范围内可全色发射的单根的微米纤维的成功制备将为实现智能化、集成化、低成本和高可靠性的微纳激光光源器件提供可靠的技术支持。

Individual Polymer Microfibers Fabricated by Melt Electrospinning: Optical Amplified, Full Color Emission, and Good Directionality for Next Flexible Excitation Sources

Integrated photonic systems would especially benefit from the availability of nano-/microscale laser sources. Single organic polymer micron fiber was successfully fabricated by high voltage melt electrospinning. The single micron fiber indicates a cylindrical structure with smooth surface. By doping different dyes in the polymer fiber, the tunable emission in the whole visible range is realized. In the condition of light pumping, amplified spontaneous emission (ASE) from the three colored micro fibers was studied in detail, they show low thresholds and high gains. In order to investigate the optical feedback cavity, finite difference time-domain (FDTD) simulations were performed to calculate electric field distribution in the microfiber. The cylindrical structure from the fiber confines the light in the cylinder and forms the loop cavity. The micro-cylinder acts like a miniaturized mirrorless cavity, where the emitted light propagates along the helical axis which behaves as a Bragg resonator. The successful fabrication of such microfibers will provide reliable technical support for the realization of intelligent, integrated, low-cost and high-reliability micro-nano laser source devices.