We present a nonlinear optical crystal-based terahertz (THz)-microfluidic chip with a few arrays of asymmetric metaatoms, elementary units of metamaterials, for the measurements of trace amount of liquid solutions. A near-field THz emission source that is locally generated in the process of optical rectification at the irradiation spots of fs laser beams induces a sharp Fano resonance and modifies the resonance frequency of the meta-atoms when the channel is filled with solutions with different concentrations. Using this chip, we successfully detected minute changes in the concentration of trace amounts of ion solutions by monitoring the shift in the resonance frequency. The detectable sensitivity of attomole order of solute in a less than 100 pL volume of the solution was achieved.

Date Published: 1 March 2019
PDF: 7 pages
Proc. SPIE 10917, Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XII, 109170J (1 March 2019); doi: 10.1117/12.2517413

Published in SPIE Proceedings Vol. 10917:
Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XII
Laurence P. Sadwick; Tianxin Yang, Editor(s)