| Metamaterial are artificially designed unit structures arranged periodically,which can regulate the electromagnetic wave characteristics on the sub-wavelength scale.They are new materials with strange electromagnetic characteristics that distinguish to many conventional materials.For the two-dimensional structure of metamaterials,it is also called as metasurfaces.Electromagnetically induced transparency（EIT）based on metasurfaces has a high Q-value,which has a broad application prospect in communication,Internet of Things and other fields.In this dissertation,the theory of electromagnetic properties such as electromagnetically induced transparency of new type of metamaterials has been deeply studied,and a series of special phenomena in quantum coherent systems have been simulated by using metamaterials.Moreover,the engineering applications of metamaterials have been explored,including multi-functional sensors,reconfigurable absorbers and so on.The main research work and innovations of this dissertation are as follows:（1）The relationship between the resonant frequencies of the four arm spiral electric and magnetic plasma polaritons and the structure is studied,and anew type of electromagnetically induced transparency with double transparent peaks is proposed,which is based on the bright-dark mode between the cut wire and the magnetic spoof localized surface plasmon（M-SLSP）,and the bright-bright mode between the electric SLSP and the square ring.We found that the electric and magnetic spoof surface plasmon polaritons excited by the spiral metasurface structure can be used to realize the coupling mode of electromagnetically induced transparency.Because the proposed electromagnetically induced transparency requires spoof surface plasmon excitation,it can also be regarded as plasmon induced transparency.In this work,the cut wire,square ring and electric spoof surface plasmon polaritons as the bright mode can be excited by the external field,while only the magnetic spoof surface plasmon polaritons can not be directly excited by the external field.We had used the coupled Lorentz oscillator model to analyze the proposed metasurface,and the simulation results agree well with the experimental results.In addition,the potential sensing applications of double electromagnetic induced transparency peaks to the permitivity of the surrounding environment are simulated numerically.（2）A logarithmic spiral structure metasurface spoof surface plasmon polariton is proposed,and high Q-value electromagnetic induced transparency is realized by using the logarithmic spiral structure.Compared with the spoof surface plasmon polaritons realized by the traditional four arm spiral structure metasurface,the advantage of the logarithmic spiral structure is that the electric dipole and magnetic dipole of the spoof surface plasmon polaritons are only excited by a single continuous metal unit at the same time,and the electromagnetically induced transparency phenomenon is directly realized in the logarithmic spiral structure,without any additional resonator.The electric dipole can be regarded as the bright mode,and the magnetic dipole can be regarded as the quasi-dark mode.In addition,the proposed electromagnetically induced transparency extends the high Q-value feature of superscattering,which makes the transmission peak frequency of EIT have a higher Q-value.The proposed metasurface is a real electromagnetically induced transparent microwave band analog studied in quantum systems,which has many potential and diverse applications.（3）A miniaturized microwave permittivity sensor based on electromagnetically induced transparency is proposed.The sensor can be fabricated by relatively low budget printed circuit board technology,and successfully simulates the EIT in a single unit microstrip feed structure.In addition,it is verified that the bright-dark mode theory in the periodic structure is still applicable to the single microstrip feed structure.Moreover,the sensor has the characteristics of small size,low budget and easy processing.By exploring the theory and potential applications of electromagnetically induced transparency,this work has made contributions to the growing research field of simulating phenomena in quantum systems with metamaterials.（4）A reconfigurable optically excited terahertz（THz）metamaterial absorber switching between single band and narrowband absorption is proposed.The absorber is composed of three layers,namely a metal plate at the bottom,a dielectric layer in the middle and a top unit connected to the dielectric substrate.The upper element of the proposed photo-excited terahertz metamaterial absorber consists of the innermost ring and the middle truncated ring high impedance surface.The embedded split ring resonator is connected with the external square ring metal resonator.It is worth noting that the four corners of the square ring metal resonator are respectively embedded in the photoconductive semiconductor（silicon）.In addition,the square air column is inserted into the dielectric substrate to promote the absorption effect of the absorber.Single band and narrowband absorption conversion can be realized by changing the silicon conductivity tuned by the optical pump beam.In addition,the proposed optically excited terahertz metamaterials have stable absorption properties at a wider incidence angle.（5）A photon spin Hall effect sensor for high precision refractive index measurement and graphene layer number measurement is proposed.The graphene material is introduced into the layered topology to excite the phenomenon of photon spin Hall effect sensor,and the horizontal polarization and vertical polarization displacement occur simultaneously.The effects of chemical potential,relaxation time and external temperature on the photon spin Hall effect sensor are also discussed.The horizontal polarization shift can be used for refractive index detection.The measurement range,sensitivity,merit and detection limit are1.1-1.5,127.85 degrees/RIU,2412 and 2.08×10-5respectively.The superior sensing performance provides a theoretical possibility for the detection of solids,liquids and gases.The offset characteristic of vertical polarization is applicable to detecting the number of layers in graphene.The measurement range is 1-9 layers and 4.54 degrees per layer. |
