Femtosecond wavelength influence on TiO2:Ag film spectral changes: Comparative study

Abstract

• High-speed nanoparticles grown is achieved by visible/UV femtosecond laser pulses in TiO 2 :Ag film. • Spectral and morphological study was carried out. • Damage-free plasmon resonance tunning was obtained by 515 nm wavelength. • 343 nm wavelength results in structural changes of the film. Plasmon resonance tuning was performed by femtosecond laser processing of silver-contained TiO 2 sol–gel films. We consider the key role of utilized wavelengths −343 nm and 515 nm, in terms of changing morphology, nanoparticles size and spectrum. The plasmon resonance peak of processed films exhibits an overall decrease (from 2.8 to 2.5 eV) with the increasing of laser fluence in the case of 515 nm. The 343 nm wavelength demonstrates a constant position of the plasmon resonance peak with a higher intensity and narrower half-breadth, which are explained by the difference of photo-thermal mechanisms activated.