Font Size: a A A

Investigation On Metamaterials And Its Application

Posted on:2010-11-13Degree:DoctorType:Dissertation
Country:ChinaCandidate:H ZhangFull Text:PDF
GTID:1118360305473664Subject:Electronic Science and Technology
Abstract/Summary:PDF Full Text Request
The materials in the nature are composed of atom or molecule, and the effects of the electromagnetic wave on materials are described by the parameters of permittivity ? and permeability ? . Metamaterials are broadly defined as artificial effectively homogenous composites or structured materials where the subwavelenth structures are served as the"artificial atom". The characteristics of metamaterials are determined by these"artificial atom": the effective permittivity ? effexhibits the effects of the electric field on metamaterials and the effective permeability ? effdescribes the response of metamaterials to the magnetic field. The emergence of metamaterials means that the media with unusual properties not readily available in natural can be obtained without prejudice to the basic rules of the physics.In this dissertation, the physics mechanism and the effective parameters of metamaterials have been comprehensively studied. According to the theoretical work, the applications of metamaterials to photonic crystals, microwave circuits and antenna have been investigated and some novel microwave components have been obtained. The original work and valuable results of this dissertation are as follows:1. The basic method of analyzing metamaterials has been established. By means of Floquet theorem, Bloch wave and transfer matrix method, the effective parameters of metamaterials is retrieved. The important point of the research is the electromagnetic parameter retrieval from the scattering parameters. The theory of the effective medium is established. Finally, the method of judging left-handed materials is concluded.2. The characteristic of resonant metamaterials has been deeply investagted. The physics mechanism of ? -negative materials, ? -negative materials and left-handed materials (LHMs) induced by thin wire and split ring resonator (SRR) is studied in detail. By means of the field distribution, the transmission parameters and effective parameters of SRR in four different polarization of the incident wave, the theory of the resonant LHMs designed by the magnetic resonant SRR and thin wire has been investigated. The complementary split ring resonator (CSRR) exhibits the dual characteristic of SRR. However, the plasma resonance of the CSRR is produced when the exterior electric field is parallel the plane of the CSRR.3. By means of the voltage wave and the current wave on the composite right/left-handed transmission line (CRLH-TL), the properties of the non-resonant metamaterials can be described. We start with the effective paramaters of ideal right-handed transmission line (RH-TL), and then the LC network of ideal left-handed transimission line (LH-TL) and its effective paremeters are obtained by the dual analysis of the RH-TL. The CRLH-TL can be seemed by the combination of RH-TL and LH-TL. The properties of the balanced and unbalanced CRLH-TL are emphatically studied.The CRLH-TL can be constructed by microstrip line with embedding lumped LC elements. The dispersion relation and the effective parameters of CRLH-TL with lumped LC elements are calculated.4. The one-dimensional photonic crystals containing LHMs or single negative (SNG) materials are investigated theoretically and experimentally, which enlarge the scope of traditional photonic crystals. 1) We study the transmission properties of the one-dimensional photonic crystals with alternating layers of LHMs and right-handed materials (RHMs), where the negative modes of the Bragg gaps and the zero volume averaged refractive index (zero- n ) gaps are observed. The thickness of the dispersive LHMs on the Bragg gap positions is discussed detailedly. The special zero-n gap has been proved to be the zero mode of the Bragg gap. 2) The conditions of discrete modes and the tunneling modes in photonic crystals containing dispersive left-handed materials are deduced, which leads to the vanishing condtion of the Bragg gap.5. The application of metamaterials in antennas and microwave circuits is proposed. 1) The circular or double linear polarization antennas are obtained by etching the CSRR on the patch antenna by adjusting the orientation of the split. 2) The super-compact substrate integrated waveguide (SIW) notch filters by embedding the CSRR are designed. 3) The dual-band, miniaturization and broadband components are respectively designed by adopting the CRLH-TL to the microwave circuits.
Keywords/Search Tags:Metamaterials, Left-handed Materials, single Negative Materials, Photonic Crystals, Split Ring Resonator, Composite Right/left-handed Transmission Line
PDF Full Text Request
Related items