A reconfigurable sandwich structure switchable DNA-based metamaterial.

In this paper, a tunable DNA-based metamaterial is designed and simulated in 170-340 THz range. This metamaterial can be transformed from an ON mode with a low resistance state of the DNA strip to its OFF mode with a high resistance state. Three Structures with containing different combinations metal layers are designed and simulated. Structure 1 with Ag/DNA/Ag and Au/DNA/Au strategies achieves field enhancement factors (FEF) 2.18 and 2.07, respectively. Structure 2 (Au/DNA/Dirac, Dirac/DNA/Au, Ag/DNA/Dirac, or Dirac/DNA/Ag) achieves the FEF values 14.11, 10.70, 13.75, or 9.62, respectively, while the FEF value of Structure 3 with Dirac/DNA/Dirac reaches 59.8. The FEF value of Structure 3 can be modulated from 59.8 to 91.96 as Fermi energy increasing from 0 to 60 meV. Moreover, the FEF value is also enhanced through increasing the magnetic field strength. The Structure 3 exhibits convertibility and sustainable modulation lines between two opposing patterns. The proposed structure reveals a switchable feature based on the resistance characteristics of DNA strips, which can be revealed as an ON/OFF switch sensor. Moreover, the switching performance of Structures 3 and 2 is significantly higher than Structure 1. Therefore, Structures 3 and 2 can be set to be an optical memristor or optical gate.