High electric field enhancement near electron-doped semiconductor nanoribbons

Adopting random phase approximation and considering radiation damping, we investigate the dynamic electric field enhancement in the vicinity of electron-doped semiconductor nanoribbons. We find that the field enhancement can reach 104 in the infrared and visible range of electromagnetic spectrum due to plasmon excitation, when radiation dominates among the damping mechanisms. In the long wavelength limit of plasmon with a specific frequency, the resonant enhancement at the optimal geometry increases with the increasing effective mass of the conducting electrons and decreases with the increasing background dielectric constant. For a fixed system, the enhancement decreases with an increasing plasmon wavenumber.