Novel Plasmonic Waveguides from Coulomb Engineered Two-Dimensional Materials

Plasmonic excitations in two-dimensional (2D) materials are strongly affected by the screening environment, which allows us to control them by the dielectric properties of the substrate. Here we present how these plasmonic excitations can be spatially confined within a homogeneous 2D material with the help of structured heterogeneous dielectric substrates. By using this environmentally-imprinted plasmonic confinement to spatially guide the propagating surface plasmons within the 2D material we can construct fundamentally new plasmonic waveguides.
Our quantum mechanical random phase approximation calculations show that this plasmonic confinement can be induced in areas of in- or decreased substrate permittivities, depending on the excitation frequency. We study in detail how the spatial extend of the environmental dielectric pattern affects these novel plasmonic waveguides and find that sub nm plasmonic confinement can be achieved.
Our proposal renders dielectric engineering a truly non-invasive way of imprinting plasmonic waveguide channels into otherwise homogeneous 2D materials with promising potential for quantum optics.