Sketch of various MIM structures, where a LSPR mode can be excited by IET.
(A, B) Au substrate coated with a thin insulating layer (~1 nm) with the antenna structure on top. (A) Spin-coated nanoparticles partially embedded in a polymer and top gated by an additional conducting layer, e.g. an evaporated gold film. (B) Lithographically etched wires. (C) Planar antenna structure on insulating substrate with sufficiently small gap. (D) Noble metal STM tip above a noble metal substrate.