Analysis Of Electromagnetic Characteristics For Left-Handed Materials Based On FDTD Method

In recent years, a new artificial composite material called left-handed metamaterial (LHM) attracted more and more attentions in the field of solid physics, material science, optics and electromagnetism. This fictitious material presented in 1967 by Russian physicist Veselago shows many abnormal electro-magnetic characteristics, which results from both the permeability and permittivity negative. These abnormal electromagnetic characteristics open a huge view for the application of LHM, and break through many traditional design in electromagnetic field, thus the LHM artificial design, electromagnetic characteristic research, and the microwave application become a hot international research field. In this paper, we made a comprehensive research on the electromagnetic characteristic of LHM from both theoretical principals and the finite-difference time domain method simulation results, and conclude the guiding sense to the applications design.Firstly, the essential principle of finite-difference time domain (FDTD) is related. According to Yee cells and difference equation, we give the 3D iterated form of free space, the solution stabilization condition and numbered dispersion minimization condition. Associated with main contents of this topic, the excitation skills, absorbing boundary condition (ABC) and Total field-Scatter field condition is introduced.Secondly, over the study of artificial metamaterial (LHM) structure design, we choose a proper constitutive equation model which is similar to the transmission line constitutive equation model of practical LHM so that a appropriate FDTD difference format for LHM is built and thus we accomplish the numerical method model to study the electromagnetic of LHM.Thirdly, we made a theoretical analysis to the LHM which prove the abnormal characteristic before we simulate the FDTD LHM numerical method model, thus we certificate the LHM and its abnormal characteristics from both theoretical and simulation method, then pointed out the value on guiding application designFinally, with the abnormal electromagnetic effects studied, we analyzed the wave energy when propagating in LHM, and compare the direction of enerya with that of phase velocity and envelop velocity, which proves the energy of wave propagating in LHM obeys the energy conservation.Since presented as a fictitious material in 1967, LHM develops fast after the theoretical and experimental proving. This paper argued the existence of LHM and its abnormal electromagnetic characteristics from the numerical simulation, and that would be help to the design and application of LHM.