Size-dependent plasmonic resonance of rectangular resonator coupled with plasmonic waveguide

摘要

In this study, we propose and investigate a rectangular resonator coupled with metal/insulator/metal-(MIM)-type plasmonic waveguides (PWGs) for application in strain or refractive index sensors. Two types of resonance modes due to different propagation directions of the surface plasmon polaritons in the rectangular resonator are analyzed through numerical simulation. The proposed device is realized by placing a rectangular resonator on MIM-type PWGs fabricated on a glass substrate, and the experimental transmission spectra of this device are found to be in good agreement with the results of numerical simulation. Two types of resonance modes with different amounts of shift are clearly observed. The change of 10nm in the size of the rectangular resonator is detected by using the resonance mode. Published under license by AIP Publishing.