摘要： Modern methods of laser-based nanocomposite fabrication and treatment rely on a deep understanding of the interplay between a set of mechanisms involved, such as nanoparticle growth and decay, material phase transformation, degradation and damage. In this work, scanning multi-pulse femtosecond laser irradiation is used for Au : T iO2 nanocomposite formation. Depending on laser scan speed two di?erent regimes are observed revealing di?erent gold nanoparticle growth rates. The regime of the remarkably fast laser-induced growth of Au nanoparticles is found to be accompanied by the cavity formation in titania ?lm around the particles. The transition between two formation regimes is found to be abrupt con?rming the catastrophic mechanism of Au nanoparticle growth. The obtained results are analyzed based on the developed numerical model including e?ects such as nanoparticle absorption, local ?eld enhancement, photo-induced free carrier generation, plasmon-assisted electron emission, and thermal heat transfer from nanoparticles towards titania matrix. Our modeling reveals the crucial role of collective thermoplasmonic e?ects caused namely by bimodal nanoparticle size distribution. The performed analysis also suggests that spall in solid state is responsible for ?nal matrix degradation if nanoparticles become large enough. The considered laser-based formation of optical nanocomposites is crucial not only for the better understanding of ultra-short laser interactions with glass-metallic nanocomposite materials, but also for numerous applications in photocatalysts, solar cells, and chemo-sensors.