Design Of A Dual-band Left-handed Metamaterial And Application On Absorber

Left-handed material (LHM) is a new kind of artificial metamaterial with negative permittivity and negative permeability simultaneously over the same band by engineering its structure, which may achieve negative refraction. Therefore it exhibits novel properties that natural ordinary medium does not possess. Since the experimental realization of the first LHM, it has been a new front field of scientific research, and has received a lot of attention and intensive study from the initial microwave bands to UHF bands and from simple plane structure to complex three-dimensional structure. In addition, the application of the left-handed materials in engineering has been a research focus.In this thesis, based on the composed theory of previous artificial left-handed materials, we propose a novel dual-band LHM and study the adjustable characteristics of the LHMs by numerical simulation. In view of the proposed LHM, we investigate its potential application in the absorbers. The obtained results may provide the helpful research ideas for designing and making dual-band left-handed metamaterials, and a theoretical basis and reference for the application in the absorber.The contents of this thesis are arranged as follow:In Chapter1, the concept, unique properties and the development of the LHM in recent years are introduced.In Chapter2, the experimental parameter retrieval method from LHMs is introduced. A single-band LHM is constructed and its electromagnetic parameters are retrieved according to the simulation results.In Chapter3, bases on the structure in Chapter2, a new dual-band left-handed material which is composed of metal cross wires and reshaped split ring resonators is designed. It is demonstrated that the proposed structure may present a Gigahertz Dual-band with negative refraction index by the retrieved S-parameter method. Moreover, we numerically investigate the influence of the main structure parameters on the negative dual bands. In Chapter4, on the basic principle of the absorber, we structure an absorber composed of the proposed LHM, which may present perfect absorption characteristics at a certain frequency band by adjusting the parameters of the structure. The simulation results show that the designed absorber may realize good absorption effect and provide a theoretical foundation for engineering applications.