Research On Terahertz Metamaterial Sensor Based On Microfluidic Technology

Metamaterials are composed of special electromagnetic materials,in which the unit structures are periodically arranged with the sub-wavelength size.They possess the characteristics such as local electric field enhancement.Terahertz wave,which is a special waveband with low photon energy in the electromagnetic wave,can be employed for the detection of biological samples.Sensors combining metamaterials with terahertz wave have achieved certain development,especially in medical detection,which have a high application value.However,the quality factors and sensitivity values of such sensors are generally low,which is the key to restricting their further development.With the maturity of microfluidic technology,which can realize the control of trace liquid samples on the micro-and sub-micron scale and provide an ideal reaction platform for most complex biochemical reactions,it meets the demand for the detection of trace liquid samples.In this work,the amalgamation of microfluidic technology and terahertz metamaterial sensors was explored to design a variety of terahertz metamaterial microfluidic sensors with distinctive structures.The main research activities included:(1)Three terahertz(THz)metamaterial microfluidic sensors were designed.The first was an irregular U-shaped structure,and a single resonance peak with an absorption rate of 99.05%at 0.99 THz was generated,enabling the detection and sensing of different concentrations of glucose solution.The next two dual-resonant peak sensors were left and right symmetrical and had two different metamaterial unit structures.The first unit structure consisted of an “I-shaped”metal and two symmetrical single-opening resonant rings,which produced two perfect absorption peaks with an absorption index of more than 99%,enabling the prediction of the refractive index of different samples with an extremely low error rate.The second unit structure was composed of three “I-shaped” metal parts,also producing two perfect absorption peaks with an absorption rate of more than 99%.Calculation showed that it could effectively distinguish between peanut oil and linseed oil.Finally,the results demonstrate that the three designed sensors have potential reference significance for rapid detection of unmarked trace substances.(2)A dual-resonant-peak terahertz metamaterial microfluidic sensor with strong stability is proposed.By analyzing various parameters of the metamaterial unit structure,the optimal combination is obtained,and the performance and stability of the sensor are then evaluated.Subsequently,stability testing of terahertz waves within a certain range of incidence verifies that the sensor can exhibit strong stability for terahertz waves with different incidence angles or polarization angles.Compared to the three terahertz metamaterial microfluidic sensors designed in Chapter 3,this sensor can provide more accurate and stable detection data.