A Novel Dual-Band Conformal Surface Plasmon Waveguide with Tunable Frequency Response in Large Scale

Abstract

A novel dual-band conformal surface plasmon (CSP) waveguide is designed and well studied in this paper. In earlier research studies, we have recognized that electromagnetic field of CSP waveguide are always confined to a sub-wavelength area and have a strong potential to be applied in device designing. However, almost all of the earlier CSP structures are mainly focus on the fundamental mode characteristics, such as fundamental resonance frequency. Here we propose a innovative dual inverted-L periodical structure with excellent performance not only on the fundamental mode but also on a new upper mode. This structure operates in microwave frequency range and shows outstanding frequency tunability characteristic. Being different from frequency characteristics in the earlier CSP waveguides, which always used to be designed single-frequency device, the novel dual-band frequency tunability characteristics of proposed dual inverted-L structure have an advantage in dual-frequency device design. In present paper, we also realize a tunable dual-frequency filter by changing the scaling factor of dual inverted-L stubs. In this case, its secondary operation frequency range can be tuned from 15 to 16.2 GHz.