Ablation and fragmentation of gold nanoparticles under intense laser irradiation in the spectral regions of the dipole and quadrupole plasmon resonances

Methods of vacuum deposition and subsequent thermal treatment of thin gold films that allow obtaining both ultimately small gold nanoparticles exhibiting spectrally narrow dipole plasmon resonances and larger nanoparticles sustaining quadrupole oscillations are proposed. The influence of high-power laser radiation on both small and large metal nanoparticles in the regions of the dipole and quadrupole resonances, respectively, is investigated experimentally. High-power laser irradiation causes ablation of small particles, while large particles experience fragmentation into particles of smaller size.