Abstract
By enabling both cavity modes and plasmonic resonance together in the designed two-handed metamaterial, we demonstrate a square-wave-like (SWL) bandpass filter with high-ratio bandwidth (HRB). Our results show that this metamaterial-based bandpass filter possesses high-ratio bandwidth of 30 GHz centered at 92 GHz, excellent transmittance beyond 87.5%, sharp transition within 1.0 GHz from -3 dB to -20 dB as upper and lower band edge transitions, and dual-band behavior. Such an HRBSWL bandpass filter can be scalable and readily applicable for the commercialized unlicensed 60 GHz spectra with a bandwidth exceeding 7 GHz, solving the challenge of conventional passive bandpass filters to allow wide bandwidths and great quality factors simultaneously.