Yousefabad Hamed Goli, Matloub Samiye, Rostami Ali
Quantum Photonics Research Lab (QPRL), University of Tabriz, Tabriz, 5166614761, Iran.
Photonics and Nanocrystals Research Lab (PNRL), University of Tabriz, Tabriz, 5166614761, Iran.
Sci Rep. 2019 Sep 9;9(1):12919. doi: 10.1038/s41598-019-49369-6.
In this work, the optical gain engineering of an ultra-broadband InGaAs/AlAs solution-processed quantum dot (QD) semiconductor optical amplifier using superimposed quantum structure is investigated. The basic unit in the proposed structure (QDs) is designed and fabricated using solution-processed methods with considerable cost-effectiveness, fabrication ease, and QDs size tunability up to various limits (0.1 nm up to the desired values), considering suitable synthesis methods. Increasing the number of QDs, the device can span more than 1.02 μm (O, C, S, and L bands) using only one type of material for all QDs, and is not restricted to this limit in case of using more QD groups. Also, it can manipulate the optical gain peak value, spectral coverage, and resonant energy for customized optical windows, among which 1.31 μm and 1.55 μm are simulated as widely-applicable cases for model validation. This makes the device a prominent candidate for ultra-wide-bandwidth and also customized-gain applications in general. Variation impact of homogeneous and inhomogeneous broadenings, injection current and number of QD groups on optical gain are explained in detail. Besides proposing a design procedure for implementation of an ultra-broadband optical gain using superimposed QDs in solution-processed technology, the proposed gain engineering idea using this technology provides practically infinite bandwidth and an easy way to realize. By introducing this idea, one more step is actually taken to approach the effectiveness of solution process technology.
在这项工作中，研究了一种采用叠加量子结构的超宽带InGaAs/AlAs溶液处理量子点（QD）半导体光放大器的光学增益工程。所提出结构中的基本单元（量子点）采用溶液处理方法进行设计和制造，具有相当高的成本效益、易于制造以及量子点尺寸可在各种限度内调节（可达所需值的0.1纳米），同时考虑了合适的合成方法。增加量子点的数量，该器件仅使用一种材料的量子点就能覆盖超过1.02微米（O、C、S和L波段），如果使用更多的量子点组则不受此限制。此外，它可以针对定制的光学窗口操纵光学增益峰值、光谱覆盖范围和谐振能量，其中1.31微米和1.55微米作为广泛适用的情况进行模拟以验证模型。这使得该器件总体上成为超宽带和定制增益应用的突出候选者。详细解释了均匀展宽和非均匀展宽、注入电流以及量子点组数对光学增益的变化影响。除了提出一种在溶液处理技术中使用叠加量子点实现超宽带光学增益的设计程序外，利用该技术提出的增益工程理念提供了实际上无限的带宽以及一种易于实现的方法。通过引入这一理念，实际上朝着提高溶液处理技术的有效性又迈进了一步。
