根据麦克斯韦方程组以及手征媒质的本构关系, 研究了手征负折射平板波导的色散特性. 通过引入归一化频率、归一化传播常数, 得到了用归一化参数表示的手征负折射平板波导的色散方程. 数值计算结果表明, 手征参数对平板波导的色散特性影响很大. 当相对手征参数约为0.047 7 时, 左旋极化波零阶模消失; 当相对手征参数大于1, 即为手征负折射媒质时, 存在零阶模. 此外, 还比较了手征负折射媒质平板波导和一般手征媒质平板波导的色散曲线变化趋势.
According to the Maxwell equations and constitutive relations in chiral medium, the paper studies the dispersion characteristic of a symmetric slab waveguide with a chiral negative refractive medium. With the normalized frequency and propagation factor, dispersion equations expressed with normalized parameters are derived in a slab waveguide with a chiral negative refractive medium. Numerical results show that the chiral parameter has great influence on the dispersion characteristic of a slab waveguide. When the relative chiral parameter is 0.047 7, the zero order mode of a left-handed polarized wave disappears. When it is greater than 1, the core becomes a chiral negative refractive medium and the zero-order mode exists. In addition, the tendency of dispersion curves in slab wave-guide is compared with a chiral negative refractive medium and that with a general chiral medium.
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2011 IEEE-APS Topical Conference on. 2011: 898-901.
