Effect of dielectric cladding on active plasmonic device based on InGaAsP multiple quantum wells.

The Surface Plasmon Polariton (SPP) planar waveguide with amorphous silicon (α-Si) cladding is studied, for empowering the device modulation response. The device is fabricated with multiple quantum wells (MQWs) as the gain media electrically pumped for compensating SPP propagation loss on Au film waveguide. The SPP propagation greatly benefits from the modal gain for the long-range hybrid mode, which is optimized by adopting an α-Si cladding layer accompanied with minimal degradation of mode confinement. The proposed structure presented more sensitive response to electrical manipulation than the one without cladding in experiment.