Abstract This paper presents a new longitudinal non-uniform compressively strained quantum well amplifier for multichannel optical signal amplification in the wavelength division multiplexing (WDM) system. Quantum transmission line modelling (Q-TLM) method is adopted to analyse the scattering spectra of electron transitions as well as the gain spectrum of QW-SOAs. It is found that the electron scattering spectrum exhibits blue shift and reduced magnitude with the decrease of carrier density while there exists red shift and enhanced magnitude with the increase of compressive strain. Furthermore, it is found that the effects of decreased carrier density on the wavelength and bandwidth of the QW-SOA gain spectrum can be compensated by increasing compressive strain. Based on the theoretical analysis, the longitudinal non-uniform (linearly and Gaussian-distributed) compressively strained quantum well amplifiers are proposed. Multichannel and dense multichannel optical signal amplification in the proposed QW-SOAs are studied and it is found that distributing non-uniform compressive strain along the quantum well amplifier cavity can effectively improve the output performance of QW-SOAs by increasing the amplification amplitude and bandwidth. The quantum well amplifier with Gaussian strain distribution has a better output spectral property for multi-channel optical signal amplification in the WDM system. These studies provide important guidance to optimize the multichannel optical signal amplification in semiconductor optical amplifiers by the band engineering.

中文翻译：

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用于波分复用系统中多通道光信号放大的非均匀应变量子阱放大器

摘要 本文提出了一种新的纵向非均匀压缩应变量子阱放大器，用于波分复用（WDM）系统中的多通道光信号放大。采用量子传输线建模（Q-TLM）方法分析电子跃迁的散射光谱以及QW-SOA的增益光谱。发现电子散射光谱随着载流子密度的降低呈现蓝移和减小的幅度，而随着压应变的增加出现红移和增强的幅度。此外，发现载流子密度降低对 QW-SOA 增益谱的波长和带宽的影响可以通过增加压缩应变来补偿。根据理论分析，提出了纵向非均匀（线性和高斯分布）压缩应变量子阱放大器。研究了所提出的 QW-SOA 中的多通道和密集多通道光信号放大，发现沿量子阱放大器腔分布非均匀压缩应变可以通过增加放大幅度和带宽来有效提高 QW-SOA 的输出性能。具有高斯应变分布的量子阱放大器对于WDM系统中的多通道光信号放大具有更好的输出光谱特性。这些研究为通过波段工程优化半导体光放大器中的多通道光信号放大提供了重要指导。研究了所提出的 QW-SOA 中的多通道和密集多通道光信号放大，发现沿量子阱放大器腔分布非均匀压缩应变可以通过增加放大幅度和带宽来有效提高 QW-SOA 的输出性能。具有高斯应变分布的量子阱放大器对于WDM系统中的多通道光信号放大具有更好的输出光谱特性。这些研究为通过波段工程优化半导体光放大器中的多通道光信号放大提供了重要指导。研究了所提出的 QW-SOA 中的多通道和密集多通道光信号放大，发现沿量子阱放大器腔分布非均匀压缩应变可以通过增加放大幅度和带宽来有效提高 QW-SOA 的输出性能。具有高斯应变分布的量子阱放大器对于WDM系统中的多通道光信号放大具有更好的输出光谱特性。这些研究为通过波段工程优化半导体光放大器中的多通道光信号放大提供了重要指导。