title: Trapping surface plasmon polaritons on ultrathin corrugated metallic strips in microwave frequencies.
abstract: It has been demonstrated that an ultrathin uniformly corrugated metallic strip is a good plasmonic waveguide in microwave and terahertz frequencies to propagate spoof surface plasmon polaritons (SPPs) with well confinement and small loss (Shen et al., PNAS 110, 40-45, 2013). Here, we propose a simple method to trap SPP waves on the ultrathin corrugated metallic strips in broad band in the microwave frequencies. By properly designing non-uniform corrugations with gradient-depth grooves, we show that the SPP waves are slowed down gradually and then reflected at pre-designed positions along the ultrathin metallic strip when the frequency varies. We design and fabricate the ultrathin gradient-corrugation metallic strip on a thin dielectric film. Both numerical simulation and measurement results validate the efficient trapping of SPP waves in broadband from 9 to 14 GHz. This proposal is a promising candidate for slow-wave devices in both microwave and terahertz regimes.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Shen
authors.forename: Pei
authors.initials: P
authors.lastname: Zhao
authors.forename: Hao Chi
authors.initials: HC
authors.lastname: Zhang
authors.forename: Tie Jun
authors.initials: TJ
authors.lastname: Cui