【摘要】 基于时域有限差分方法,模拟分析了位于介质材料上的杆形和蝴蝶结形两种金纳米天线及杆形天线阵列.结果表明天线近场光斑直径约可以达到波长的1/11,蝴蝶结形天线的光斑强度可以比入射光场增强91倍.杆形天线阵列仍可以实现这种增强效应.蝴蝶结形天线中光场增强最高可以达到28000倍,而且局域化的光场可以耦合到天线臂上的纳米颗粒.更多还原

【Abstract】 Nano-rod and bow-tie antennas that are gold nano-antennas on dielectric material and the nano-rod antenna arrays are numerically studied by the finite difference time domain method in three dimensions.The light field that project on the antennas can be confined to a spot with subwavelength width(~λ/11),and the light intensity can be enhanced to 91 times the incident light in the near-field with the bow-tie antenna.The enhancement also exists in the antenna arrays.The highest enhancement of the light intensity at the bow-tie antenna gap can reach about 28000 times,and the localized field can be coupled to a nano-particle near the antenna gap.更多还原