Abstract

Coupling surface plasmons (SPs), collective charge oscillations produced by the resonant interaction of light and free electrons on the interface of metallic and dielectric materials, to frequency comb [2,3] creates numerous advantages. However, the superior performance of the frequency comb, such as absolute frequency uncertainty, high frequency stability and narrow linewidth, could deteriorate during photon-plasmon-photon conversion process. This was recently confirmed by exploiting plasmonic extraordinary transmission through a subwavelength plasmonic hole array [4]. Then, the frequency comb was utilized for high-resolution phase spectroscopy in plasmonics for realizing picometer resolution plasmonic ruler [5]. Here, we report that the frequency comb at a plasmonic structure can be also used for high-resolution gas detection even with small target volume of the gas.

© 2019 IEEE