Enhancing the linear absorption and tuning the nonlinearity of TiO ₂ nanowires through the incorporation of Ag nanoparticles

We report on the enhanced linear absorption and modified nonlinear absorption of TiO₂ nanowires coated with Ag nanoparticles. Experimental results indicated that the coated Ag nanoparticles significantly increased the linear absorption of the nanostructures in the wavelength range of visible light. Z-scan experiments showed that when the excitation energy increased, the nonlinear absorption of the TiO₂ nanowires changed from reverse-saturable absorption to saturable absorption. When Ag nanoparticles were coated on the TiO₂ nanowires, the reverse-saturable absorption was significantly inhibited. The as-prepared nanostructures may find potential applications in the field of solar cells and all-optical switching.