Abstract

A finite-difference time-domain (FDTD) approach is used to investigate the excitation of surface plasmon polaritons (SPPs) of gold circular arc aperture array deposited on an optical fiber endface. The impact of the radiuses of big and small circular arc apertures, the center distance of two circular arc apertures and the array periodicity on extraordinary optical transmission (EOT) are discussed. It is found that the structure with the radiuses of the big and small two circular arc apertures of 100 nm and 80 nm, the center distance of the two circular arc apertures of 100 nm and the period of 425 nm has a better EOT. This EOT can provide the basis of a sensitive refractive index sensor. The proposed optical sensor is compact and has the potential to be used in biomedical applications, having a sensitivity of (324 ± 62) nm per refractive index unit (RIU) as found through the variation of a transmission maximum with the wavelength.

© 2017 Optical Society of America