偏振方向对H型金纳米结构光热性质影响的研究

Influence of Polarization of Light on Photo-thermal Properties of Au H-shaped Nanostructure

采用离散偶极近似方法(DDA)计算了在不同偏振方向的入射光激励下,H型金纳米结构在水介质环境中的共振吸收光谱及近区电磁场分布;在此基础上,利用付里叶热传导定律数值模拟了该结构产生的热效应。结果表明:该金属纳米结构在近红外波段存在两个主要等离激元共振模式,在单一波长的共振光激励下,改变入射光的偏振方向可调节吸收峰值大小;同时,也可以有效地调节结构的近场电磁场耦合作用,在结构周围形成高度限定的局域热增强现象,在较大的温差范围内调控该结构及其周围介质环境的局域温度。

Absorption spectrometry under the water and plane polarized and distribution of electromagnetic fields from a H-shaped gold nanostructure incident light excitation were carried out by taking advantage of discrete di- pole approximation （DDA）. Furthermore, the thermal enhancement of this nanostructure was also simulated through the use of Fourier~ law of heat conduction. The numerical simulations show that this nanostructure have two main surface plasmon resonance modes in the near infrared wave band, and the absorption peak intensity are significantly affected by the polarization of the resonance light on a single wavelength. Moreover, as electromag- netic energy can be effectively converted into the polarization of the resonance light, strongl thermal energy due to the effect of near-field coupling by adjusting ylocalized confinement and highly enhancement of thermal energy around the nanostructure can be realized. Since this ture, the temperature increment on the nanostructure over a wide range. localized thermal enhancement occurred in the nanostruc- and its surrounding medium environment can be controlled