基于半导体量子点的特性,结合光纤渐逝波耦合器,提出了一种新型的光纤放大器件,它将以溶液形式的硫化铅(PbS)半导体量子点材料沉积于耦合器熔锥区,信号光和抽运光通过渐逝波共同与半导体量子点材料相互作用,实现光的放大作用。PbS量子点材料是采用工艺容易控制的反胶束法制备的,通过透射电镜(TEM)测量得到其粒子尺寸小于10 nm。利用工作波长为980 nm,功率为30 mW的半导体激光器抽运光源对该光纤放大器抽运,在1310 nm波段得到了大于4 dB的增益,这是半导体量子点尺寸效应引起的光谱蓝移现象的体现。因此,这种有源区短、器件结构紧凑的光纤放大器在高速、宽带光纤接入等领域具有重要的实际意义和应用价值。
Based on the characteristic of semiconductor quantum dots and evanescent wave fiber coupler, a novel fiber amplifier was proposed. This semiconductor quantum dots fiber amplifier (SQDFA) was fabricated by depositing PbS quantum dots prepared by solution route on the fused taper region. Optical amplification was realized by interaction between the signal evanescent field and pump's in the quantum dots. PbS quantum dots were synthesized by simply reverse micelle method. The size of PbS quantum dot was less than 10 nm measured by transmission electron microscope (TEM). The optical gain more than 4 dB was obtained at 1310 nm pumped by semiconductor-laser at 980 nm with 30 mW. The optical gain at 1310 nm shows the spectral blue shift resulted from quantum size effect. This compact quantum dots fiber amplifier has potential applications in high-speed broadband access network.