Nanowerk June 27, 2022
Researchers in Japan have developed a nonlinear optical crystal-based compact terahertz (THz)-microfluidic chip with several I-design meta-atoms for attomole (amol)-level sensing of trace amounts of solution samples. The chip consists of a metallic strip with a micrometer-sized gap sandwiched by other metallic strips. A point THz source locally generated by optical rectification at the irradiation spot of a femtosecond-pulse laser beam induced a tightly confined electric-field mode at the gap regions and modified the resonance frequency when a microchannel fabricated along the space between the metallic strips was filled with solutions. Using this chip, they could detect minute changes in the concentration of trace amounts of ethanol- and glucose-water solutions and mineral water by measuring the shift in the resonance frequencies. They demonstrated detection capability improvement of approximately one order of magnitude compared to the performance of existing chips. The work would accelerate the development of microfluidics integrated with THz technology, such as lab-on-a-chip devices and THz micro total analysis systems…read more. Open Access TECHNICAL ARTICLEÂ
Schematic and optical image of a terahertz (THz) microfluidic chip… Credit: Journal of Physics: Photonics, Volume 4, Number 3Â