Opt Lett. 2023 Jul 1;48(13):3507-3510. doi: 10.1364/OL.491357.
The refractive index is a critical parameter in optical and photonic device design. However, due to the lack of available data, precise designs of devices working in low temperatures are still frequently limited. In this work, we have built a homemade spectroscopic ellipsometer (SE) and measured the refractive index of GaAs at a matrix of temperatures (4 K < T < 295 K) and photon wavelengths (700 nm < λ < 1000 nm) with a system error of ∼0.04. We verified the credibility of the SE results by comparing them with afore-reported data at room temperature and with higher precision values measured by vertical GaAs cavity at cryogenic temperatures. This work makes up for the lack of the near-infrared refractive index of GaAs at cryogenic temperatures and provides accurate reference data for semiconductor device design and fabrication.
折射率是光学和光子器件设计中的一个关键参数。然而，由于缺乏可用数据，工作在低温下的设备的精确设计仍然经常受到限制。在这项工作中，我们构建了一个自制的光谱椭圆偏振仪（SE），并在一个温度矩阵（4K<T<295K）和光子波长（700nm<λ<1000nm）下测量了 GaAs 的折射率，系统误差约为 0.04。我们通过将 SE 结果与室温下先前报道的数据以及低温下垂直 GaAs 腔测量的更高精度值进行比较，验证了 SE 结果的可信度。这项工作弥补了低温下 GaAs 的近红外折射率的不足，为半导体器件设计和制造提供了准确的参考数据。
