The mode characteristics and magnetic distributions of a chiral negative refraction parallel-plate waveguide under perfect magnetic conductor (PMC) boundary are studied theoretically. With boundary conditions of PMC, dispersion relations and electromagnetic fields are obtained. Using the dispersion curves, if the chirality parameter κ >1, curves become concave-down in some regions and the refractive index of left circularly polarized (LCP) wave is negative. It imply that chiral medium can realize negative refraction. The cutoff frequency is no longer the conventionally defined frequency when propagation constant is zero. According to the relations between propagation constant β and wavenumbers k+ and k−, the dispersion curves are divided into three regions. Amplitudes of magnetic field components on the first-order even mode and first-order odd mode are plotted respectively. Chatacteristics of the magnetic field components are discussed and compared with the conventional chiral slab waveguide. It is shown that Hy and Hz are zero at x/d = ±0.5. It indicates that they satisfy the PMC boundary conditions and,due to the existence of magnetic current, Hx is not zero at the interface.
MA Quan-wen, XIAO Zhong-yin, XU Xiao-xue, XU Wen-jie, MA Xiao-long, LIU De-jun, WANG Zi-hua
. Modes and fields for a chiral negative refraction parallel-plate waveguide under PMC boundary[J]. Journal of Shanghai University, 2015
, 21(5)
: 579
-587
.
DOI: 10.3969/j.issn.1007-2861.2014.03.013
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