| Nano-photonic structures have unique optical characteristics.Photonic crystals composed of dielectric nano-photonic structures possess photonic band gap.Periodic modulation of the incident electromagnetic wave results in a band structure that regulates photon propagation.The metal-dielectric-metal plasma structures can support the surface plasmon mode that forms a local high-intensity electric field.Both of the two kinds of nano-photonic structures have important application prospects in sensing,radiation modulation,photoelectric detection,high-resolution imaging,and electromagnetic wave absorbers.This thesis proposed to introduce active materials into nano-photonic structures to regulate the spatial permittivity of the nano-photonic structures thus the resonance response of the nano-photonic structures can be modulated.The photonic crystal structure was proposed to enhance the light absorption of single-layer graphene and used in refractive index sensing.Vanadium dioxide?VO2?phase change material was introduced into the plasma structure to modulate the absorption peak in the visible-near infrared band.The doped semiconductor supporting the epsilon-near-zero?ENZ?mode was combined with the metamaterial to achieve broadband absorption,while the gate voltage was used to regulate the absorption intensity,which was applied to heat radiation devices.The critical coupling method was used to enhance the light absorption intensity of single-layer graphene.The single-layer graphene was placed on top of a metal plasma structure.The Fermi level of graphene was changed by an external electric field or doping to control the resonance frequency of graphene that realizes the adjustment of the absorption peak.The photonic crystal structure composed of a cylindrical array of titanium dioxide?Ti O2?is placed on top of a single layer of graphene.The graphene and metal aluminum substrate were separated by an aluminum oxide?Al2O3?layer,which provides a weak Fabry-Perot?FP?resonance.Optimizing the thickness of Al2O3 to generated strong coupling between guided mode resonance and FP resonance can improved the light absorption intensity of single-layer graphene.Furthermore,the sensing characteristics of graphene has also been studied.Researched the photonic crystals of silicon?Si?structure to enhance the light absorption of single-layer molybdenum disulfide?Mo S2?.The vanadium dioxide?VO2?phase change material was used to control the resonance response of the plasma structure.Two kinds of plasma structures were designed:aluminum nano-hole arrays and aluminum cylindrical array structure.Broadband absorption was achieved in the near-infrared band,and adjusted by changing the spatial dielectric constant through phase change.The electric field distribution at the absorption peak was analyzed,and the influence of different structural parameters on the absorption performance of the microstructure was numerically simulated.Moreover,the spectral response of the plasma structure to the polarization angle and the incident angle was analyzed.The ENZ mode supported by indium tin oxide?ITO?material to achieved broadband absorption in a metamaterial structure.The gate voltage changes the carrier concentration in ITO to change the dielectric constant,which modulated the absorption intensity.The electric field distribution in the ENZ mode was analyzed.The influence of different structural parameters on the absorption characteristics of metamaterial structures was numerically analyzed while the absorption spectra at different polarization angles and incident angles were analyzed and tested.The ITO film was designed for thermal radiation control devices and studied for the radiation energy spectrum with various temperature.Absorption spectra under different structural parameters were analyzed and simulated.The thermal radiation spectrum of thermal radiation devices at 1300K temperature with different incident angles,under TE and TM mode,respectively,was analyzed and tested. |
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