We propose an Fe-doped, InGaAs-based semiconductor heterostructure optimized for the application as an ultrafast photoconductor and investigate its optical as well as THz properties. A sample series with varying doping concentration is grown by molecular-beam epitaxy. After examination of its static optical properties, the pump-induced intraband carrier dynamics are investigated via optical pump-THz probe measurements. Here, we observe conductivity decay times as low as 0.23 ps which are attributed to electron capture into Fe-related defects. These results are corroborated by monitoring the corresponding interband dynamics via all-optical pump-probe measurements. In addition, the competitiveness of THz detectors fabricated from a subset of these samples is demonstrated by integrating them into a standard time-domain spectrometer.

中文翻译：

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新型 Fe 掺杂 InGaAs 量子光电导体的超快太赫兹电导动力学

我们提出了一种掺杂 Fe 的、基于 InGaAs 的半导体异质结构，该异质结构针对作为超快光电导体的应用进行了优化，并研究了其光学和太赫兹特性。通过分子束外延生长具有不同掺杂浓度的样品系列。在检查其静态光学特性后，通过光泵浦太赫兹探针测量研究了泵浦诱导的带内载波动力学。在这里，我们观察到电导率衰减时间低至 0.23 ps，这归因于电子捕获到与 Fe 相关的缺陷中。这些结果通过全光泵浦探头测量监测相应的带间动态得到证实。此外，通过将这些样本的一个子集制造的太赫兹探测器集成到标准时域光谱仪中，证明了它们的竞争力。