Thermally and optically tunable sub-terahertz superconducting fishnet metamaterial

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2018-01-15
SABAH, Cumali
MULLA, Batuhan
Altan, Hakan
Ozyuzer, Lutfi
In this paper, a novel fishnet metamaterial structure is designed and analyzed under different material combinations and under different active controlling techniques. The results indicate that, the proposed fishnet metamaterial has a single resonance with double negativity at 0.39 THz when quartz substrate and aluminum is utilized in the design. Moreover, when the metallic parts are replaced with YBCO, the proposed design also exhibits double negativity with a stronger resonance and can be used as a switch between the double negative and single negative modes if the temperature is altered. In addition to these, when substrate (quartz) is replaced with MgO, the resonance shifts from 0.39 THz to 0.26 THz and shows double negativity. Moreover, switching properties under illumination can also be obtained when the silicon is utilized in the design (MgO-YBCO combination). According to these results, it is found that, in the case that the conductivity of silicon exceeds a certain value, the character of the resonance changes from double negative to the single negative mode.
PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS

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Citation Formats
C. SABAH, B. MULLA, H. Altan, and L. Ozyuzer, “Thermally and optically tunable sub-terahertz superconducting fishnet metamaterial,” PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS, pp. 46–53, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/35862.