Calculated Optical Properties of Dielectric Shell Coated Gold Nanorods  

作　　者：曹敏 王孟 顾宁 

机构地区：[1]State Key Laboratory of Bioelectronics and Jiangsu Laboratory for Biomaterials and Devices, Southeast University, Nanjing 210096 [2]School of Science, Nantong University, Nantong 226007

出　　处：《Chinese Physics Letters》2009年第4期143-146,共4页中国物理快报（英文版）

基　　金：Supported by the National Natural Science Foundation of China under Grant No 90406023, and the National Basic Research Programme of China under Grant No 2006CB933206.

摘　　要：Optical absorption spectra of dielectric shell coated gold nanorods are simulated using the discrete dipole ap- proximation method. The influence of the aspect ratio, shell thickness, dielectric constant of the shell, and surrounding medium on the longitudinal resonance mode is investigated. It is found that the coated dielectric shell does not affect the trend in the dependence of resonance position on the aspect ratio, while it broadens the resonant line width and reduces the sensitivity of plasmon resonance in response to changes of the surrounding medium. F^arthermore, the difference of dielectric constants between the shell and surrounding medium plays an important role in determining the resonance position. The screening effect of the dielectric shell tends to be less apparent for a thicker shell thickness.Optical absorption spectra of dielectric shell coated gold nanorods are simulated using the discrete dipole ap- proximation method. The influence of the aspect ratio, shell thickness, dielectric constant of the shell, and surrounding medium on the longitudinal resonance mode is investigated. It is found that the coated dielectric shell does not affect the trend in the dependence of resonance position on the aspect ratio, while it broadens the resonant line width and reduces the sensitivity of plasmon resonance in response to changes of the surrounding medium. F^urthermore, the difference of dielectric constants between the shell and surrounding medium plays an important role in determining the resonance position. The screening effect of the dielectric shell tends to be less apparent for a thicker shell thickness.Optical absorption spectra of dielectric shell coated gold nanorods are simulated using the discrete dipole ap- proximation method. The influence of the aspect ratio, shell thickness, dielectric constant of the shell, and surrounding medium on the longitudinal resonance mode is investigated. It is found that the coated dielectric shell does not affect the trend in the dependence of resonance position on the aspect ratio, while it broadens the resonant line width and reduces the sensitivity of plasmon resonance in response to changes of the surrounding medium. F^arthermore, the difference of dielectric constants between the shell and surrounding medium plays an important role in determining the resonance position. The screening effect of the dielectric shell tends to be less apparent for a thicker shell thickness.Optical absorption spectra of dielectric shell coated gold nanorods are simulated using the discrete dipole ap- proximation method. The influence of the aspect ratio, shell thickness, dielectric constant of the shell, and surrounding medium on the longitudinal resonance mode is investigated. It is found that the coated dielectric shell does not affect the trend in the dependence of resonance position on the aspect ratio, while it broadens the resonant line width and reduces the sensitivity of plasmon resonance in response to changes of the surrounding medium. F^urthermore, the difference of dielectric constants between the shell and surrounding medium plays an important role in determining the resonance position. The screening effect of the dielectric shell tends to be less apparent for a thicker shell thickness.

关 键 词：gamma-ray bursts GAMMA-RAYS RELATIVITY 

分 类 号：O484.41[理学—固体物理] TN011[理学—物理]