Fig. 1. Schematic of the studied optical device based on the Ag MNPs chain-graphene-Au MNPs chain, where vibrational molecules are placed on the surface of graphene lattice. The nanoelectrodes of our device formed by two parallel linear chains of (A) Ag MNPs and (B) Au MNPs are separated by a distance (h) and incorporated in a suspended graphene single layer. We shine only the Ag chain (A) by an external light beam, and the output detector is placed at the end of the Au chain (B).

Fig. 2. Variation of the real part of the permittivity of the graphene-molecules hybrid system for molecule concentrations S = 0 nm⁻³, S = 0.01 nm⁻³, and S = 0.014 nm⁻³, where the chemical potential of graphene is μ = 0.21 eV. (a) ℏω_m = 280 meV and (b) ℏω_m = 284 meV.

Fig. 3. Transmission coefficient (T) as a function of frequency for the three selected molecules that are characterized by ℏω_m = 280 meV, ℏω_m = 284 meV, and ℏω_m = 288 meV, respectively. The chemical potential of the graphene layer is equal to 0.21 eV at room temperature.

Fig. 4. Transmission coefficient (T) as a function of frequency for the three selected molecules characterized by ℏω_m = 280 meV, ℏω_m = 284 meV, and ℏω_m = 288 meV, respectively. The chemical potential of the graphene layer is equal to 1.21 eV at room temperature.

Fig. 5. Transmission spectra calculated at the end of chain (B) with and without molecules, and the chemical potential of graphene is μ = 1.21 eV.

Fig. 6. Transmission spectra for different value of h when ω_m = 280 meV and μ = 1.21 eV.

Fig. 7. Transmission spectrum of light passing through the second chain (B) for the two values of the chemical potential μ = 0.21 eV and μ = 1.21 eV.

Fig. 8. Variation of the absorption in graphene (red line), transmission of light passing through Ag chain (red dashed line), and transmission at the end of the Au chain (black line) for (a) ℏω_m = 280 meV and (b) ℏω_m = 284 meV when the chemical potential μ = 0.21 eV.

Table 1. Plasma Frequency ω_p and Damping Factor γ for Ag and Au Metals