Phenomenological study of gold elliptical nanohole array as a plasmonic rotation sensor

Abstract

Plasmonic engineering has opened up new opportunities in the field of subwavelength photonics for solving real world problems. The analysis of rotation is a key concept across aerospace, medical and industrial fields. Here we present a novel multiwavelength optical rotation sensor that makes use of the rich plasmonic properties of plasmonic nanohole arrays. A quantitative evaluation is provided on the extraordinary optical transmission as well as quality factor of the key wavelengths as a function of rotation. In order to investigate the origin of the peak wavelengths, we have studied the electrical field intensity of the elliptical nanohole array. Three surface plasmon resonance (SPR) peaks corresponding to wavelengths of 631.5 nm, 752 nm and 1090.5 nm are identified which are independent of rotation angle. The third peak at 1090.5 nm has the highest transmission angular dependency whereas the first peak at 631.5 nm has the greatest Q-factor. It is shown that the shape of the electric field profile can be deduced from the transmission. The present results show that elliptical nanohole arrays are suitable as a method for electromagnetic interference (EMI) resistant remote rotation sensing as well as for use on photonic integrated circuits as part of post-Moore optoelectronic devices. Furthermore, the results presented here have a large implication on photolithography as well as biosening applications, in particular ELISA.