We describe a new approach to modeling the optoelectronic properties of a terahertz-frequency quantum cascade laser (THz QCL) based on a quantum transmission line modelling (Q-TLM) method. Parallel quantum cascade transmission line modeling units are employed to describe the dynamic optical processes in a nine-well THz QCL in both the time and frequency domains. The model is used to simulate the current–power characteristics of a QCL device and good agreement is found with experimental measurements, including an accurate prediction of the threshold current and emitted power. It is also confirmed that the Q-TLM model can accurately predict the Stark-induced blue shift of the emission spectrum of the THz QCL with increasing injection current. Furthermore, we establish the new Q-TLM model to describe the properties of a THz QCL device incorporating a photonic lattice patterned on the laser ridge, by linking the transmission line structure to each scattering module. The predicted effects of the lattice structure on the steady-state emission spectra of the THz QCL, including the side-mode suppression, are found to be in good agreement with experimental results. Our Q-TLM modeling approach is a promising tool for the future design of THz QCLs and analysis of their temporal and spectral behaviors.

中文翻译：

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太赫兹量子级联激光器输出特性的量子传输线建模与实验研究

我们描述了一种基于量子传输线建模 (Q-TLM) 方法对太赫兹频率量子级联激光器 (THz QCL) 的光电特性进行建模的新方法。采用并行量子级联传输线建模单元在时域和频域中描述九井太赫兹 QCL 中的动态光学过程。该模型用于模拟 QCL 器件的电流-功率特性，并且与实验测量结果非常吻合，包括阈值电流和发射功率的准确预测。也证实了Q-TLM模型可以准确预测随着注入电流的增加，THz QCL发射光谱的Stark诱导蓝移。此外，我们建立了新的 Q-TLM 模型，通过将传输线结构连接到每个散射模块来描述 THz QCL 器件的特性，该器件包含在激光脊上图案化的光子晶格。发现晶格结构对 THz QCL 稳态发射光谱的预测影响，包括边模抑制，与实验结果非常吻合。我们的 Q-TLM 建模方法是未来太赫兹 QCL 设计及其时间和光谱行为分析的有前途的工具。发现与实验结果吻合良好。我们的 Q-TLM 建模方法是未来太赫兹 QCL 设计及其时间和光谱行为分析的有前途的工具。发现与实验结果吻合良好。我们的 Q-TLM 建模方法是未来太赫兹 QCL 设计及其时间和光谱行为分析的有前途的工具。