Designing Graphene-Based Multi-Mode Acousto-Plasmonic Devices

We design multi-mode acousto-plasmonic devices based on the surface acoustic wave (SAW) assisted gratings, required for exciting and tuning plasmonic waves on the graphene surface. The SAW assisted gratings can be realized and controlled by applying an appropriate AC signal to the electrode pairs. Three types of SAW assisted gratings are proposed, including uniform and dual-segment gratings as well as chirped gratings. The behavior of the graphene plasmonic waves depends on the employed gratings scheme. Simulations show that the dual-segment and the chirped gratings result in multimode plasmonic spectra. These reconfigurable multi-mode acousto-plasmonic devices, with multiple controlling parameters, can lead to the realization of efficient multi-mode refractive index sensors, higher data transmission capability in plasmonic waveguides, and higher electrical controllability of plasmonic switches. All simulations are done by the finite element method.