摘要
在亚波长金属单狭缝聚焦结构的基础上,提出了一种易于集成加工的亚波长金属单狭缝填充金属条的超分辨率聚焦结构。采用时域有限差分法(FDTD)对该结构的聚焦特性进行了仿真分析。通过分析研究聚焦结构参数对聚焦效果的影响,获得了超衍射极限的聚焦光斑,该聚焦光斑的归一化光强I为4.5、焦半径(FWHM)为300 nm(小于λ/2,λ=632.8 nm)。对于±10 nm的尺寸与定位误差对结构的聚焦特性影响甚微。该模型聚焦结构的横向尺寸仅为2.0μm,适用于纳米光子学、集成光子电路等领域,具有较高的应用价值。
A super-resolution focusing and easy integrated sub-wavelength metal single-slits containing mental strip structure is proposed based on sub-wavelength metal slit focusing structure. The focusing properties of the structure are simulated and analyzed by using electromagnetic field simulation software finite difference time domain （FDTD）. Through the analysis of structural parameters of focusing structure influence on the focusing effect, a high focusing intensity of I=4.5 and a small spot size with full width half maximum （FWHM） of 300 nm （lass than λ/2, λ = 632.8 nm） is achieved. Meanwhile, the structure＇s deviation and positioning accuracy of ±10 nm have little effect on the focusing property. Such a focusing structure with the predicted focusing efficiency has potential practical applications in nanophotonics and integrated photonics due to the small lateral dimension size of only about 2.0 μm.
出处
《激光与光电子学进展》
CSCD
北大核心
2014年第6期167-171,共5页
Laser & Optoelectronics Progress
基金
国家科技重大专项(2009ZX02206)
关键词
光学器件
超分辨率聚焦
时域有限差分法
金属狭缝结构
optical devices
super-resolution focusing
finite difference time domain method
metal slit structure
