中国物理B ›› 2011, Vol. 20 ›› Issue (3): 37303-037303.doi: 10.1088/1674-1056/20/3/037303
周飞1, 李志远1, 刘晔2
Zhou Fei(周飞)a), Liu Ye(刘晔)a)b), and Li Zhi-Yuan(李志远)a)†
摘要: We theoretically investigate surface plasmon resonance properties in Au and Ag cubic nanoparticles and find a novel plasmonic mode that exhibits simultaneous low extinction and high local field enhancement properties. We analyse this mode from different aspects by looking at the distribution patterns of local field intensity, energy flux, absorption and charge density. We find that in the mode the polarized charge is highly densified in a very limited volume around the corner of the nanocube and results in very strong local field enhancement. Perturbations of the incident energy flux and light absorption are also strongly localized in this small volume of the corner region, leading to both low absorption and low scattering cross section. As a result, the extinction is low for the mode. Metal nanoparticles involving such peculiar modes may be useful for constructing nonlinear compound materials with low linear absorption and high nonlinearity.
中图分类号: (Collective excitations (including excitons, polarons, plasmons and other charge-density excitations))