Ultrathin, highly flexible and optically transparent terahertz polarizer based on transparent conducting oxide

Abstract

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.

Fully Optically Tunable and Flexible Composite Films for Enhanced Terahertz Control and Multifunctional Terahertz Devices

“…To verify the bending performance of the VO 2 /PVP film, the device was examined through the THz transmission change of the VO 2 /PVP film, while the THz transmission of the initial VO 2 /PVP film before bending was used as the control. Figure d shows the THz transmission change of the VO 2 /PVP film that remained relatively unchanged up to 500 bending cycles . The tiny discrepancy observed in the THz transmission of the VO 2 /PVP film at each measurement was mainly due to a slight deformation of the PI film after repeated bending.…”

“…Figure 2d shows the THz transmission change of the VO 2 /PVP film that remained relatively unchanged up to 500 bending cycles. 15 The tiny discrepancy observed in the THz transmission of the VO 2 /PVP film at each measurement was mainly due to a slight deformation of the PI film after repeated bending. The details are described in the Supporting Information.…”

“…Terahertz (THz) technology has been developed as a new cutting-edge technology in the recent decade , with wide applications such as THz spectroscopy, − THz imaging, , and THz communication. , For THz applications, various THz devices, such as filters, , polarizers, , and modulators, − have emerged with newly advanced structures and materials. Traditional THz devices that are fabricated on rigid substrates with a high refractive index, such as silicon and quartz, , mainly lack mechanical flexibility and are always single-functional, thus limiting their applications. ,− In contrast to these rigid THz devices, flexible THz devices hold a high position for the next generation of THz devices because of their mechanical flexibility and tunable properties for curved THz components with improved performances when incorporated with active media.…”

“…Terahertz (THz) technology has been developed as a new cutting-edge technology in the recent decade 1,2 with wide applications such as THz spectroscopy, 3−7 THz imaging, 8,9 and THz communication. 10,11 For THz applications, various THz devices, such as filters, 12,13 polarizers, 14,15 and modulators, 16−19 have emerged with newly advanced structures and materials. Traditional THz devices that are fabricated on rigid substrates with a high refractive index, such as silicon and quartz, 20,21 mainly lack mechanical flexibility and are always single-functional, thus limiting their applications.…”

Broadband, optically transparent and highly flexible multispectral beam splitter based on Ag nanowires/graphene composite film for hybrid optical systems

“…For THz applications, THz systems commonly require various passive THz devices [17][18][19], including THz reflector, THz polarizer, THz lens, THz beam splitter, etc. Among these devices, THz beam splitter plays a key role in THz systems, such as THz spectroscopy and THz communication [20,21].…”