Research Institute of Superconductor Electronics, Nanjing University, Nanjing 210023, China.
Purple Mountain Laboratories, Nanjing 211111, China.
ACS Appl Mater Interfaces. 2023 Jul 12;15(27):32875-32884. doi: 10.1021/acsami.3c04096. Epub 2023 Jun 30.
Optical antireflection has been employed for a variety of applications in terahertz spectroscopy and detectors. However, current methods encounter challenges in terms of cost, bandwidth, structural complexity, and performance. In this study, a low-cost, broadband, and easily processed THz antireflection coating scheme based on the model of impedance-matching effect is proposed, using a 6 wt % d-sorbitol-doped poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (s-PEDOT:PSS) film. By adjusting the thickness of the s-PEDOT:PSS film, these biocompatible conductive polymers enable a significant reduction of Fresnel reflection and operate over a broad bandwidth between 0.2 and 2.2 THz. Applying the antireflective coating to the surface of the sample substrate and electro-optic probe crystal in THz spectroscopy and near-field imaging shows that the spectral resolution is significantly improved, and the devices exhibit more excellent intended performance. The findings of this study could aid in improving the measurement capability of various THz time-domain spectroscopy and imaging system.
光学抗反射已经在太赫兹光谱学和探测器的各种应用中得到了应用。然而，目前的方法在成本、带宽、结构复杂性和性能方面都面临挑战。在这项研究中，提出了一种基于阻抗匹配效应模型的低成本、宽带和易于处理的太赫兹抗反射涂层方案，使用了 6wt%的 d-山梨醇掺杂聚(3,4-乙二氧基噻吩)：聚(4-苯乙烯磺酸盐)(s-PEDOT：PSS)薄膜。通过调整 s-PEDOT：PSS 薄膜的厚度，这些生物相容性的导电聚合物可以显著减少菲涅尔反射，并在 0.2 到 2.2THz 的宽频带上工作。在太赫兹光谱学和近场成像中，将抗反射涂层应用于样品基底和电光探针晶体的表面，结果表明，光谱分辨率得到了显著提高，器件表现出了更优异的性能。这项研究的结果可以帮助提高各种太赫兹时域光谱学和成像系统的测量能力。
