A Terahertz Metamaterial Absorber-Based Biosensor for Ascorbic Acid

A novel metamaterial sensor with nearly perfect absorption based on extraordinary reflection has been proposed and implemented for terahertz sensing. The biosensing model was simulation-validated and metamaterial sensors were fabricated on the polyimide substrate using femtosecond laser processing technology. Gradient concentrations of ascorbic acid (AA) were deposited onto the metamaterial sensor using the drop sample drying method and measured with a terahertz frequency-domain spectroscopy system. A strong linear correlation was observed between the shift in resonance peak frequency and the concentrations during the experiment, it is an effective and simple means for measuring AA concentrations without any modification.