Fig. 3. Effects of applied bias on the plasmonic modes of the NM and the spherical dimer.

(A and B) TDDFT results for the absorption spectra of a cylindrical NM (R₁ = 41.3 Å, R₂ = 47.7 Å, R₃ = 61 Å) and a spherical dimer (R = 21.7 Å) with gap width S = 6.4 Å. (C) Absorption cross section per unit length σ/l calculated with QCM for the cylindrical NM with the same geometry as in (A). (D) Time evolution of the dipole induced in the NM of (A) by an incident pulse of light resonant with the ${\mathrm{\omega }}_{-}^{-}$ plasmon mode and polarized perpendicularly to the symmetry axis. The bias is applied at time t = 2 fs. The values of the applied bias are detailed in the insets.