基于内嵌旋转银纳米方块圆形纳米腔的折射率传感器（英文）

Refractive Index Sensor Based on Circular Nanocavity Embedded with Tilted Silver Nanocube

本文设计了一个基于内嵌可旋转银纳米方块圆形纳米腔的金属-介质-金属波导滤波器,并用时域有限差分算法进行了表征。由于旋转的银纳米方块破坏了圆形纳米腔原有的对称稳态磁场分布,因而产生了一种新的振动模式。这种新的振动模式依赖于内嵌旋转银纳米方块的旋转角度和边长。与没有嵌入银纳米方块和嵌入银纳米方块没有旋转时的金属-介质-金属波导滤波器相比,内嵌入旋转的银纳米方块的金属-介质-金属波导滤波器对周围介质折射率的微小变化更加敏感。因此,该结构在生物传感器方面具有潜在应用。

A novel plasmonic sensor of circular nanocavity embedded with an Ag nanocube based on the metal-insulator-metal （MIM） waveguide was characterized by the finite-difference time-domain method. Since the tilted Ag nanocube breaks the symmetric steady-state magnetic field distribution, a new resonant mode occurs in the circular nanocavity. The resonance depends on the rotation angle and length of the cube. The MIM waveguide with a circular nanocavity embedded with a tilted Ag nanocube is more sensitive to small refractive index changes that fill the nanocavity than the MIM waveguide with a empty circular nanocavity and the MIM waveguide with circular nanocavity symmetrically embedded with an Ag nanocube. A potential application to biosensors has therefore been established.