Gao Zhen, Gao Fei, Zhang Baile
Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
Centre for Disruptive Photonic Technologies, Nanyang Technological University, Singapore 637371, Singapore.
Sci Rep. 2016 Apr 15;6:24447. doi: 10.1038/srep24447.
We experimentally demonstrate that multiple high-order spoof localized surface plasmons (spoof-LSPs) modes can be supported on a complementary metallic spiral structure, which were absent in the previously reported spoof-LSPs modes. Through exact numerical simulations and near-field imaging experiments, we directly observe these high-order spoof-LSPs modes at microwave frequencies. We also show that these higher-order spoof-LSPs modes exhibit larger frequency shifts caused by the local environmental refractive index change than the previously reported low-order spoof-LSPs modes. Hence the complementary MSS may find potential applications as plasmonic sensor in the microwave and terahertz frequencies.
我们通过实验证明，在互补金属螺旋结构上可以支持多种高阶类局域表面等离子体激元（spoof-LSPs）模式，而这些模式在先前报道的spoof-LSPs模式中并不存在。通过精确的数值模拟和近场成像实验，我们在微波频率下直接观测到了这些高阶spoof-LSPs模式。我们还表明，与先前报道的低阶spoof-LSPs模式相比，这些高阶spoof-LSPs模式因局部环境折射率变化而表现出更大的频移。因此，互补金属螺旋结构在微波和太赫兹频率下作为等离子体传感器可能具有潜在应用。
