研究目的
To study the dynamic and static processes occurring in disordered multiparticle colloidal Ag aggregates with natural structure and affecting their plasmonic absorption spectra under pico- and nanosecond pulsed laser radiation, as well as the physical origin responsible for these processes.
研究成果
The study concludes that the mechanisms of laser modification of disordered multiparticle colloidal Ag aggregates depend on the laser pulse duration, leading to changes in the resonant properties of particles due to their heating and melting (picosecond pulses) or particle shifts in resonant domains (nanosecond pulses). These mechanisms result in the formation of a narrow dip in the plasmonic absorption spectrum near the laser radiation wavelength, with the effect of polydispersity on the photochromic reaction also being significant.
研究不足
The study is limited by the complexity and interconnection of related processes in the interaction of pulsed laser radiation with plasmonic nanoparticle aggregates. The model simplifies some aspects of the real physical processes, such as the finite relaxation time of the elasticity modulus of the adsorption layer and the size dependence of melting temperature.
1：Experimental Design and Method Selection:
The study employs an optodynamic model to simulate the interaction of pulsed laser radiation with multiparticle aggregates of plasmonic nanoparticles, considering thermodynamic, optical, physico-chemical, and mechanical processes.
2：Sample Selection and Data Sources:
A set of 2000 aggregates generated with the method of Brownian dynamics, consisting of 50 Ag nanoparticles with radii from 2 nm to 8 nm for polydisperse aggregates and 5 nm for monodisperse aggregates.
3：List of Experimental Equipment and Materials:
The model uses parameters such as the Hamaker constant for silver, the elasticity modulus of particle adlayers, and the dielectric constant of the interparticle medium.
4：Experimental Procedures and Operational Workflow:
The model solves a system of ordinary differential equations describing the motion of each particle in an aggregate under the influence of various forces, including van der Waals, elastic, optical, viscous friction, and tangential interparticle friction forces.
5：Data Analysis Methods:
The extinction spectra of aggregates are calculated using the coupled dipoles method, and the results are averaged over the set of aggregates and over three mutually perpendicular polarizations of the incident laser radiation.
独家科研数据包，助您复现前沿成果，加速创新突破
获取完整内容
