Terahertz integrated waveguide sensor based on a metal rod array for phase sensitive fluid detection

Abstract

A metal rod array (MRA) is experimentally demonstrated as a miniaturized terahertz (THz) waveguide with an extended optical path length and successfully incorporated into microfluidics for liquid molecule sensing. The THz waves guided along the MRA is operated by the transverse-electric (TE) polarization and the resonance transmission within the structural slits is approved in the study. Three layers of MRA support the THz waves to sufficiently overlap the fluid molecules embedded among the rods and strongly enhance the phase change by approximately one order of magnitude. The presentation shows the detection limit of a liquid analyte is less than 0.1 mmol, corresponding to 2.7 μmol/mm2.