Department of Physics, Shahid Beheshti University, G.C., Evin, Tehran, 19839, Iran.
Department of Physics and Astronomy, Seoul National University, Seoul, 151-747, Korea.
Sci Rep. 2019 Feb 4;9(1):1378. doi: 10.1038/s41598-018-37499-2.
A novel plasmonic interferometric sensor intended for application to biochemical sensing has been investigated experimentally and theoretically. The sensor was included a slit surrounded by rectangular grooves using a thick gold film. A three-dimensional finite difference time-domain commercial software package was applied to simulate the structure. The Focused ion beam milling has been used as a mean to fabricate series of rectangular plasmonic interferometer with varying slit-groove distance L. Oscillation behavior is shown by transmission spectra in a broadband wavelength range between 400 nm and 800 nm in the distance between slit and grooves. Red-shifted interference spectrum is the result of increasing refractive indices. The proposed structure is functional from visible to near-infrared wavelength range and yields a sensitivity of 4923 nm/RIU and a figure of merit as high as 214 at 729 nm wavelength. In conclusion, this study indicates the possibility of fabricating a low cost, compact, and real-time high-throughput plasmonic interferometer.
一种新型的等离子体干涉传感器，旨在应用于生化传感，已经进行了实验和理论研究。该传感器包括一个用厚金膜包围的狭缝和矩形槽。采用三维有限差分时域商业软件包对结构进行模拟。采用聚焦离子束铣削作为一种手段，制造了一系列具有不同狭缝-槽距 L 的矩形等离子体干涉仪。在 400nm 至 800nm 的宽带波长范围内，在狭缝和沟槽之间的距离处，通过传输光谱显示出了振荡行为。随着折射率的增加，出现了红移干涉光谱。所提出的结构在可见到近红外波长范围内具有功能，在 729nm 波长处的灵敏度为 4923nm/RIU，品质因数高达 214。总之，这项研究表明了制造低成本、紧凑、实时高通量等离子体干涉仪的可能性。
