In this paper, for the first time, a highly ultra-broadband QD-SOA based on superimposed Quantum Dots has been proposed to accomplish a broader optical gain spectra range of almost 3.5 µm from blue to Mid-infrared, considering solution-processed nanotechnology as a simple and cost-effective fabrication method. The realization of the ultra-broadband optical gain can be accomplished by the superimposition of the various size-distributed QD groups made of different materials in a way that the broader energy span is covered as a consequence of the variation of the bandgap energy for each QD groups. To this end, different QD groups made of Bismuth Tellurium Sulphide (Bi₂Te_3-xS_x) and Cadmium Tellurium Sulphide (CdTe_1-xS_x) in the ZnS shell implemented in the active region of QD-SOA have been superimposed, in which the radii of each QD groups can be easily distributed due to incorporating solution-processed method. The performance of the proposed QD-SOA has been modelled based on the developed rate equation framework by assuming inhomogeneous broadening of energy levels as a result of the size distribution of QDs and the superimposition of various QD groups. Furthermore, the bandwidth and, the spectral range, and the flatness of the optical gain in the QD-SOA can be managed by the number of QD groups, the percentage of Tellurium and Sulphur in the Bi₂Te_3-xS_x and CdTe_1-xS_x alloys, and the size distribution of each QD groups.

在本文中，首次提出了一种基于叠加量子点的高超宽带 QD-SOA，以实现从蓝色到中红外近 3.5 µm 的更宽光学增益光谱范围，考虑溶液处理纳米技术作为一种简单且具有成本效益的制造方法。超宽带光学增益的实现可以通过叠加由不同材料制成的各种尺寸分布的 QD 组来实现，由于每个 QD 的带隙能量的变化，可以覆盖更宽的能量跨度团体。为此，由硫化铋（Bi ₂ Te _3-x S _x）和硫化镉（CdTe _1-x S _x) 在 QD-SOA 的有源区实现的 ZnS 壳中已经叠加，其中每个 QD 基团的半径可以很容易地分布，因为结合了溶液处理方法。所提出的 QD-SOA 的性能已基于开发的速率方程框架进行建模，假设由于 QD 的尺寸分布和各种 QD 组的叠加而导致能级的不均匀展宽。此外，QD-SOA 中的带宽、光谱范围和光学增益的平坦度可以通过 QD 组的数量、Bi ₂ Te _3-x S _x和 CdTe中碲和硫的百分比来管理_1-x S _x合金，以及每个 QD 组的尺寸分布。