Extraction of dielectric and magnetic material properties for a periodic hole array THz filter

With the increase in optical applications in the terahertz frequency range there is a greater need for devices that work at these frequencies. One such device which has applications which range from spectroscopy to imaging is the band pass filter. The frequency selective nature of this component can be used for filtering noise during signal processing or can be even used for reducing radiation background levels for imaging purposes [1, 2]. The simplest form of this filter structure has been shown to be that of a free-standing metal sheet with a hole array. The frequency selective nature of the filter is realized by changing the structural parameters of the hole array with respect to the propagating input THz wave. Due to the sub-millimeter wave nature of the radiation the patterns are easier to fabricate for low frequency terahertz radiation applications (