A Broadband FSS Bandstop Filter in Terahertz Region

摘要

A wideband bandstop filter using frequency selective surface (FSS) operating in the terahertz (THz) frequency range has been reported. The simulation results show that it has a 3-dB bandwidth of 22.9 THz over the resonating frequency of 24.1 THz. The transmission stopband lesser than 30dB has been achieved along with a fractional bandwidth of 95%. The structure has been analyzed under the variations of several geometrical parameters. The structure is found to behave as wideband stopband filter till $40 ^{o}$ incident angle. The structure offers wide stopband till $15 ^{o}$ polarization angle. Being ultra-thin $( sim lambda /12)$ and simple in nature, the filter can be very easy to realize in practice. The structure finds its application in spectroscopy, imaging etc.