Terahertz antireflection coatings employing off-the-shelf adhesive tapes.

We demonstrate the feasibility of making antireflection coatings (ARCs) for terahertz (THz) light using multilayered polymer films from commercial adhesive tapes. Efficient and low-cost ARCs in the THz range are not conveniently available. Our economical approach can mitigate many of the experimental challenges posed by Fresnel reflection. Harnessing a time-domain THz spectrometer, we demonstrate the performance of several types of multilayer coatings on a variety of substrates. By varying layer stacking and thicknesses, spectral performance can be tuned and optimized for specific applications. Good agreement is found between experimental measurement and analytic calculations evaluating the performance of these multilayer tape ARCs.