Color-changeable properties of plasmonic waveguides based on Se-doped CdS nanoribbons

The color-changeable optical property induced by the resonance of surface-plasmon polaritons (SPPs) based on a ternary alloy CdS0.65Se0.35 (CdSSe) nanoribbon partly placed on an Ag film was reported. The spectroscopic redshift of in situ CdSSe photoluminescence under different incident laser powers was characterized by using scanning near-field optical microscopy. The propagation length, mode area, and confinement factor of the SPPs were also investigated. The trade-off between the spectroscopic shift and plasmonic resonance was demonstrated with the Franz-Keldysh effect and simulated by using the finite-difference time-domain method. The suggested plasmonic structure provides valuable information for the implementation of photonic integrated nanocircuits, especially for the color-changeable plasmonic device.