Tuneable complementary metamaterial structures based on graphene for single and multiple transparency windows

Abstract

Novel graphene-based tunable plasmonic metamaterials featuring single and multiple transparency windows are numerically studied in this paper. The designed structures consist of a graphene layer perforated with quadrupole slot structures and dolmen-like slot structures printed on a substrate. Specifically, the graphene-based quadrupole slot structure can realize a single transparency window, which is achieved without breaking the structure symmetry. Further investigations have shown that the single transparency window in the proposed quadrupole slot structure is more likely originated from the quantum effect of Autler-Townes splitting. Then, by introducing a dipole slot to the quadrupole slot structure to form the dolmen-like slot structure, an additional transmission dip could occur in the transmission spectrum, thus, a multiple-transparency-window system can be achieved (for the first time for graphene-based devices). More importantly, the transparency windows for both the quadrupole slot and the dolmen-like slot structures can be dynamically controlled over a broad frequency range by varying the Fermi energy levels of the graphene layer (through electrostatic gating). The proposed slot metamaterial structures with tunable single and multiple transparency windows could find potential applications in many areas such as multiple-wavelength slow-light devices, active plasmonic switching, and optical sensing.

Tunable bandwidth of double electromagnetic induced transparency windows in terahertz graphene metamaterial

“…These behaviors can be attributed to change in resonant frequency of graphene cutwire, in which the resonant frequency can be written as f f ffiffiffiffiffi E F p . 38,43 During the blue-shi, moreover, the amplitude of the transparency peak is almost unchanged, while the corresponding bandwidth gradually widens, as shown in Fig. 7(b).…”

Graphene Plasmonics: A Platform for 2D Optics

“…The tunable plasmonic resonances in graphene metasurfaces with various geometries have been intensively applied for significantly modulating the reflection, transmission, and absorption of light in the forms of plasmonically induced transparency (EIT) spectra and perfect absorbers. [87,89,[128][129][130][131][132][133][134][135][136][137][138][139][140]…”

Dual-band high-frequency metamaterial absorber based on patch resonator for solar cell applications and its enhancement with graphene layers

“…Obtaining a high conductivity by using graphene is one of the main advantage of the graphene based structures. [19,20]. Correspondingly, one can control the electromagnetic wave by controlling the conductivity (and relatedly dielectric constant) of the graphene in which it provides additional flexibility in the design and fabrication of various device configurations.…”