Figure 2
From: Highly sensitive and selective sugar detection by terahertz nano-antennas
The THz measurements for sugars with and without nano-antennas.
(a) Schematic of the THz detection of sugar molecules using a nano-antenna array-based sensing chip. The small cubes represent crystallized molecules of sugar and the THz wave is normally incident on the chip. Inset is a microscopic image of the nano-slot-antenna array for fructose. (b) Normalized THz spectra measured for a bare Si wafer used as a substrate and 250 mg/dL of glucose on the same Si substrate. (c) Normalized THz spectra measured with the glucose antenna for D-glucose and (d) sucrose molecules. (e) The changes in the maximum values of the normalized transmittances are plotted for D-glucose, sucrose and cellulose as a function of the molecular concentration level. (f) Frequency shifts at the maximum transmittance for three samples are plotted.
