Research Progress of Terahertz Metamaterial Biosensors

Terahertz (THz) wave, refers to the frequency range of 0.1 similar to 10 THz electromagnetic wave located in the electromagnetic spectrum between infrared and microwave. The photon energy of the Terahertz wave is lower than that of visible light, and the corresponding energy of 1 THz is only about 4. 14 meV, which means the damage caused by radiation to tissues and organs in living organisms would be reduced greatly and will not ionize the biological molecules. Therefore, this band has important potential application value in basic science, human security, dangerous goods detection, high-speed communication and medical imaging. In the application of medical and biological detection, it is usually necessary to detect trace amounts of analytes, which requires higher sensitivity and detection accuracy. However, the existing detection methods are affected by the low reliability of terahertz wave intensity detection. Metamaterial-based biosensing can achieve sub-wavelength resolution by enhancing local electromagnetic resonance, which greatly improves the sensor's resolution and sensitivity and has attracted widespread attention. The metamaterial is a kind of artificial periodic structure that can enhance the local electromagnetic resonance response, realize sub-wavelength resolution and improve the sensor' s resolution and sensitivity. The terahertz metamaterial sensor provides a new detection method for the field of biosensing, which has the advantages of high sensitivity, fast response speed, and label-free detection. With the rapid development of micro-nano processing technology, the cost of making metamaterial terahertz sensors continues to decrease, which has great potential application value in the field of biomedicine. Research on terahertz sensors based on metamaterials has become a very popular international frontier direction. However, there are no reports on the latest research progress of terahertz metamaterial sensors. Therefore, this paper has collected and sorted out relevant information and reviewed the latest applications of the terahertz metamaterial sensor in various biological detection scenarios, including medical diagnosis, food safety, pesticide detection and so on. Finally, the development and application prospect of Terahertz metamaterials in biosensors are summarized and prospected. This paper will provide an important reference for people to grasp the latest application progress of Terahertz metamaterial biosensors and guide the development and application of Terahertz metamaterial biosensors.