Structure Design And Performance Simulation Of Photonic Devices Based On All-dielectric Metamaterials

The demand for information technology in the recent year is increasing.People have higher and higher requirements for information transmission capacity and transmission rate.Traditional optical components can no longer meet the needs of current communication systems.Researchers have begun to study new materials for communication and other aspects.In traditional optical elements,an optical system needs to be composed of multiple optical elements,resulting in a complex and bulky optical system.Some optical applications based on metamaterials have solved these problems very well.There are many metamaterial-based optical structures that artificially lay out the surface structure to distinguish it from natural materials,which can achieve the control properties that many natural materials do not have.By adjusting the size,shape and position of the surface micro-nano structure,the optical element can realize the adjustment of the characteristics of the phase,amplitude and polarization of the incident light,so as to achieve the purpose of adjusting the optical wavefront,laying a foundation for the multi-functional optical element.Traditional optical components require multiple components in series to accumulate phases.New optical components based on metamaterials are more integrated and smaller,and a single component has the potential to achieve multiple optical functions,thereby greatly reducing the volume of the optical system.It improves the control efficiency and can more perfectly adapt to the rapid development of information technology.It can be used in nonlinear optics,optical sensors,and high-resolution imaging and other aspects.This paper mainly discusses the application and structural design methods of one-dimensional and two-dimensional metamaterials and their performance simulation.The main contents can be summarized as follows:(1)Firstly,the research background and current status of metamaterials are introduced.One-dimensional metamaterials and two-dimensional metamaterials are discussed respectively.The basic classification methods and research methods,as well as numerical calculation methods are introduced respectively.Different research theory are introduced,and their applications are proposed separately.(2)A one-dimensional metasurface silicon-based photonic crystal nanobeam with high quality factor and high optomechanical coupling efficiency is proposed.The design principles,theoretical background knowledge,and calculation methods are introduced.The optical and mechanical mode field modes,related parameters,and coupling modes of one-dimensional silicon-based photonic crystals are analyzed theoretically.The one-dimensional silicon-based crystals nanobeam have a resonance wavelength of 1550 nm,and produce a high quality factor of 1.06 × 106 and a high optical-mechanical coupling rate of 3210 k Hz.Silicon-based integrated technology has features such as high speed,low loss,and compatibility with CMOS processes,and will provide certain support for integrated silicon-based photon chaotic sources.(3)A series of two-dimensional metasurface signalfocal and multifocal metalenses based on computer-generated holography are proposed.The basic design theory and focusing physical mechanism of metalenses are introduced.The surface phase distribution of the metalens in the range of visible light from 500 nm to 750 nm was studied by computer-generated holography method.The unit cell structure of single focus and multi-focus metalenses was arranged according to the Pancharatnam-Berry phase distribution.In addition,the metalens focusing ability and focusing effect for single focus and multi focus have improved the focusing efficiency by about 15% compared with previous work,and also broke the traditional optical diffraction limit,simplified the design process,and can flexibly design the metasurface structure.The broadband performance of multi-wavelength con-focal metalenses was discussed.It also achieved good focusing effects and broke the optical diffraction limit,providing certain technical support for future optical topologies and optical storage.