Terahertz-wave near-field imaging with subwavelength resolution using surface-wave-assisted bow-tie aperture
Terahertz-wave near-field imaging with subwavelength resolution using surface-wave-assisted bow-tie aperture
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DOI：
10.1063/1.2387984
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发表时间：
2006-11-13
影响因子：
4
通讯作者：
Ito, Hiromasa
中科院分区：
文献类型：
--
作者：
Ishihara, Kunihiko;Ohashi, Keishi;Ito, Hiromasa
我们利用金属薄膜中同心周期结构环绕的蝴蝶结状光圈，实现了亚波长分辨率的太赫兹波近场成像。具有同心周期槽的亚波长孔径，即所谓的靶眼结构，在表面波的共振激发引起的衍射极限之外，显示出极大的增强透过率。此外，蝴蝶结光圈在金属尖端表现出非凡的场增强，这提高了透射率和亚波长的空间分辨率。我们在牛眼结构中引入了蝴蝶结光圈，在近场区域获得了高空间分辨率(类似于lambda/17)。获得了207微米波长下亚波长金属图案(图案宽度=20微米)的太赫兹波近场图像。(C)2006年美国物理研究所。
We demonstrate the terahertz-wave near-field imaging with subwavelength resolution using a bow-tie shaped aperture surrounded by concentric periodic structures in a metal film. A subwavelength aperture with concentric periodic grooves, which are known as a bull's eye structure, shows extremely large enhanced transmission beyond the diffraction limit caused by the resonant excitation of surface waves. Additionally, a bow-tie aperture exhibits extraordinary field enhancement at the sharp tips of the metal, which enhances the transmission and the subwavelength spatial resolution. We introduced a bow-tie aperture to the bull's eye structure and achieved high spatial resolution (similar to lambda/17) in the near-field region. The terahertz-wave near-field image of the subwavelength metal pattern (pattern width=20 mu m) was obtained for the wavelength of 207 mu m. (c) 2006 American Institute of Physics.