利用时域有限差分方法研究了金纳米球、金纳米球壳及多层球壳的消光特性及电场分布.结果表明:金纳米颗粒的几何参量对消光峰的位置有显著影响.随着SiO2核心半径的增大,金纳米壳的消光峰显著红移.随着金核心半径的增大,gold—silica—gold多层球壳消光谱的低能峰显著红移,而高能峰微弱蓝移.
The optical properties and electric field distribution of gold nanospheres, gold nanoshells, and gold-silica-gold multilayer nanoshells were studied using finite-difference time-domain method. The experiment results showed that the geometric parameters of gold nanoparticles had a significant impact on the position of extinction peak. When the radius of SiO2 core increased, the extinction peak of gold nanoshell had a blue shift; when the radius of Au core increased, the extinction lowenergy peak of gold-silica-gold multilayer nanoshells had a red shift, and the extinction high-energy peak had a weak blue shift.