Numerical analysis of DNA-based implementation for terahertz switchable metamaterial absorber

In this paper, a tunable and switchable metamaterial absorber is proposed and simulated based on DNA materials, graphene and Dirac semimetal. Resonance behaviors of this absorber can be switched from an absorption peak to an absorption band based on the properties of DNA particles: high resistance mode and low resistance mode. The absorption peak and absorption band are excited by the local surface plasmons (LSP) modes and surface plasmon polariton (SPP) modes resonance. The carrier mobility mu of graphene layers is optimized in three regions (Dirac semimetal support area, DNA support area, and suspended area) to enhance the absorption peak and band. These resonance behaviors based on the high and low resistance modes of DNA particles are optimized through changing the external voltage conditions of graphene layers. Moreover, the Fermi energy of Dirac semimetal strips can also be used to optimize these performances. The proposed structure can be applied as optical memristors or optical gates based on the DNA switching property.