Reprogrammable control of electromagnetic spectra based on time-coding plasmonic metamaterials

Programming electromagnetic spectra have become key technology affecting the development of the information industry, arousing widespread interest of researchers. Here, we propose a route to realize a programmable spectrum based on time-coding spoof surface plasmon polaritons (SSPPs) to implement the customized harmonic generations and amplitude manipulations. The proposed time-coding SSPPs are experimentally demonstrated to flexibly control both frequencies and amplitudes of the harmonics, providing the possibility of reprogrammable outputs of different spectra. In addition, two kinds of improved time-coding SSPP structures are presented, which can be applied to realize reprogrammable spectra without the fundamental component and with customized asymmetric spectra.