论文标题
紧张和放松的直接带隙GESN半导体中的中红外发射和吸收
Mid-infrared emission and absorption in strained and relaxed direct bandgap GeSn semiconductors
论文作者
论文摘要
通过独立的工程应变和组成，这项工作表明并研究了从硅上种植的GESN层的中红外范围内的直接带隙发射。我们将室温发射波长延伸到〜4.0μm以上的生长后应变弛豫中，均匀的SN含量为17％。根据温度依赖性的光致发光，吸收测量和理论模拟讨论了控制光发射的基本机制。无论应变和组成如何，这些分析都确认在4-300 K的探测温度范围内总是观察到单峰发射，排除缺陷和杂质相关的发射。此外，由于应变松弛，发现载流人损失到热激活的非辐射重组通道中被大大最小化。吸收测量值验证了与光致发光数据紧密相匹配的细胞和松弛样品中的直接带隙吸收。这些结果突出了GESN半导体作为多功能构建块的强大潜力，可扩展，紧凑和与硅兼容的中红外光子学和量子光电。
By independently engineering strain and composition, this work demonstrates and investigates direct band gap emission in the mid-infrared range from GeSn layers grown on silicon. We extend the room-temperature emission wavelength above ~4.0 μm upon post-growth strain relaxation in layers with uniform Sn content of 17 at.%. The fundamental mechanisms governing the optical emission are discussed based on temperature-dependent photoluminescence, absorption measurements, and theoretical simulations. Regardless of strain and composition, these analyses confirm that single-peak emission is always observed in the probed temperature range of 4-300 K, ruling out defect- and impurity-related emission. Moreover, carrier losses into thermally-activated non-radiative recombination channels are found to be greatly minimized as a result of strain relaxation. Absorption measurements validate the direct band gap absorption in strained and relaxed samples at energies closely matching photoluminescence data. These results highlight the strong potential of GeSn semiconductors as versatile building blocks for scalable, compact, and silicon-compatible mid-infrared photonics and quantum opto-electronics.
