Active modulation of surface plasmon resonance wavelengths by applying an electric field to gold nanoparticle-embedded ferroelectric films

In this study, we use organic chemical addition and phase-transfer methods to prepare lead zirconate titanate (PZT) composite films embed with large numbers of gold nanoparticles (Au NPs). The surface plasmon resonance (SPR) wavelength in the nanocomposite materials can be modulated cyclically through the application of an external electric field. The Au NPs are embedded homogeneously in the PZT matrix; the PZT crystal size and the metal particle size both increase upon increasing the annealing temperature. The Au/PZT nanocomposite film displays apparent piezoelectric properties in its ferroelectric hysteresis curve that can be used in the active modulation of the SPR wavelengths. The major factor influencing the shift in the SPR absorption in the Au/PZT nanocomposite films is the change in the refractive index of the host PZT matrix.