Multifunctional terahertz devices hold great promise for terahertz (THz) optical systems. Here, we present an ultrathin, highly flexible and optically transparent terahertz polarizer based on tin-doped indium oxide (ITO) and flexible conformal films of polyethylene terephthalate. The flexible optical transparent polarizer (FOTP) was theoretically investigated and experimentally characterized by UV–vis spectrophotometry and THz time-domain system. In the FOTP, THz conductivity of ITO films is mainly dominated by DC conductivity. The FOTP reveals a high optical transmittance of more than 60% in the visible region, a high extinction ratio of about 20 dB in the 0.1 THz–2.5 THz and a low insertion loss below 2 dB in the 0.1 THz–1.4 THz. The proposed FOTP can significantly improve the overall performance of THz optical systems and be easily fabricated by commercial display techniques. Our concept opens up a new window for highly flexible and optically transparent THz devices.

中文翻译：

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基于透明导电氧化物的超薄，高柔韧性和光学透明太赫兹偏振片

多功能太赫兹设备在太赫兹（THz）光学系统中具有广阔的前景。在这里，我们介绍了一种超薄，高度柔性和光学透明的太赫兹偏振片，它基于掺锡的氧化铟（ITO）和聚对苯二甲酸乙二醇酯的柔性共形膜。通过紫外可见分光光度法和太赫兹时域系统对柔性光学透明偏振片（FOTP）进行了理论研究和实验表征。在FOTP中，ITO薄膜的太赫兹电导率主要由直流电导率决定。FOTP显示出在可见光区域的透光率高达60％以上，在0.1 THz-2.5 THz的消光比约为20 dB，在0.1 THz-1.4 THz的消光损耗低于2 dB。提出的FOTP可以显着改善THz光学系统的整体性能，并且可以通过商业显示技术轻松制造。我们的概念为高度灵活和光学透明的THz设备打开了一个新窗口。