An Electrically Reconfigurable Plasmonic Lens using Graphene

Taking advantage of nonuniform conductivity distributions on graphene, the realization of a plasmonic lens with electrically tunable focal lengths is proposed and numerically investigated. The philosophy of the reconfigurable lens focusing is the nonlinear relation between surface plasmon polaritons (SPP) wave index and chemical potential of graphene. Upon tuning the gate voltage between graphene and ground, the graphene-based Maxwell Fisheye lens can be transformed to Luneburg lens. The ray-tracing method is employed to find out the exit angles for rays with different incident angles. Full-wave simulations showing excellent focusing performances are achieved.