金/银双金属薄膜对表面等离子体共振特性的影响——与金和银单金属薄膜的比较

The Effect of Au/Ag Bimetallic Thin-Films on Surface Plasmon Resonance Properties Comparing with Those of Au and Ag Single Thin-Films.

作者信息

Kim Seon Hoon, Kim Tae Un, Jung Haeng Yun, Ki Hyun Chul, Kim Doo Gun, Lee Byung-Teak

机构信息

Laser Research Center, Korea Photonics Technology Institute, Gwangju, 61007, Korea.

Department Materials Science and Engineering, Chonnam National University, Gwangju, 61186, Korea.

出版信息

J Nanosci Nanotechnol. 2018 Mar 1;18(3):1777-1781. doi: 10.1166/jnn.2018.14954.

DOI:10.1166/jnn.2018.14954

PMID:29448658

Abstract

The surface plasmon resonance (SPR) properties of Au/Ag bimetallic thin-film nanostructures were investigated to improve the chemical stability and the figure of merit (FOM) in the SPR sensors. The SPR characteristics such as resonance angle, extinction ratio, and full width half maximum (FWHM) were calculated by the simulation of the finite-difference time-domain method and were measured using the laser with a 632.8 nm wavelength in the Kretschmann-Raether configuration. The measured resonance angle, extinction ratio, FWHM of Au(20 nm)/Ag(20 nm) thin-film nanostructure were found to be 44°, 0.8, and 1.4°, respectively. The FOM values were determined to be 56.9 for Au/Ag bimetallic thin-film, 47.9 for Au(50 nm) single thin-film, and 89.1 for Ag(50 nm) single thin-film. Also the sensitivity values were about 53.5, 57.0, and 57.8°/RIU for Au(50 nm), Ag(50 nm), and Au(20 nm)/Ag(20 nm) thin-film nanostructures in the SPR sensors, respectively. The SPR properties of Au/Ag bimetallic thin-film nanostructures were compared with those of the Au and Ag single thin-film nanostructures.

摘要

研究了金/银双金属薄膜纳米结构的表面等离子体共振（SPR）特性，以提高SPR传感器的化学稳定性和品质因数（FOM）。通过有限时域差分法模拟计算了共振角、消光比和半高宽（FWHM）等SPR特性，并在Kretschmann-Raether配置下使用波长为632.8 nm的激光进行测量。发现金（20 nm）/银（20 nm）薄膜纳米结构的测量共振角、消光比和FWHM分别为44°、0.8和1.4°。金/银双金属薄膜的FOM值确定为56.9，金（50 nm）单薄膜为47.9，银（50 nm）单薄膜为89.1。此外，SPR传感器中，金（50 nm）、银（50 nm）和金（20 nm）/银（20 nm）薄膜纳米结构的灵敏度值分别约为53.5、57.0和57.8°/RIU。将金/银双金属薄膜纳米结构的SPR特性与金和银单薄膜纳米结构的SPR特性进行了比较。