Trapping effect and trajectory control of surface plasmon polaritons in a metal-dielectric-metal waveguide

Abstract

A nonlinear optical-magnetic manipulation scheme is proposed to realize the low-loss surface plasmon polaritons (SPPs) trapping in metal-dielectric-metal (MDM) waveguide, based on double electromagnetically induced transparency (EIT) and cross-phase modulation (CPM), theoretically. Using incoherent pumping, the Ohmic loss of SPPs is compensated. The huge nonlinearity in the system balances the diffraction of the SPPs, and a SPPs soliton is obtained. With the SPPs solitons, we realize the trapping of another weaker SPPs via CPM. We find that the trapped SPPs have a similar profile as the stronger SPPs, thus, the profile of trapped SPPs can be controlled even can be focused when being defused. We also show that the SPPs will deflect in an external gradient magnetic field, and the trajectory of the SPPs can be manipulated dynamically via adjusting the magnetic field gradient. The results obtained here may have great potential in future on-chip circuitry.