In this work, we derived the modal dispersion relation for TEm modes for a symmetric slab waveguide constructed from SiO2 dielectric guiding core material with lossy left-handed material (LHM) as cladding and substrat...In this work, we derived the modal dispersion relation for TEm modes for a symmetric slab waveguide constructed from SiO2 dielectric guiding core material with lossy left-handed material (LHM) as cladding and substrate, and the power confinement factor. The dispersion relations and the power confinement factor were numerically solved for a given set of parameters: allowed frequency range;core’s thicknesses;and TEm mode order. We found that the real part of the effective refractive index decreased with thickness and frequency increase. Moreover, the imaginary part (extinction coefficient) of the effective refractive index has very small values for all thickness in the frequency ranges, which means the waveguide structure is transparent for the used frequencies. The waveguide structure offers good guiding power for all thickness in the frequency range with low power attenuation. The real part of the effective refractive index increases with the increase of mode order, and the power confinement factor decreases with the increase of mode order.展开更多
为了改善单极子天线的辐射特性,通过对左手材料开路电流环谐振器(Split Ring Resonator,SRR)的结构及其电磁特性研究,提出一种新的复合天线设计思路,即将单个SRR或多个SRR与单极子天线复合。利用电磁理论和HFSS软件仿真得到工作频率为3....为了改善单极子天线的辐射特性,通过对左手材料开路电流环谐振器(Split Ring Resonator,SRR)的结构及其电磁特性研究,提出一种新的复合天线设计思路,即将单个SRR或多个SRR与单极子天线复合。利用电磁理论和HFSS软件仿真得到工作频率为3.52GHz的这种复合天线的各项参数。仿真结果表明复合天线中SRR的个数对谐振天线的频率影响很小,其增益也基本不变。与单独的单极子天线相比,复合天线尺寸更小,类似电小天线,因此可被应用在电性能类似单极子天线,而天线尺寸又要求较小的领域。展开更多
Transmission properties of fractal Cantor distribution with left-handed materials （LHM） are investigated. The transmittance and reflectance spectra can be calculated by using the optical transmission matrix method. ...Transmission properties of fractal Cantor distribution with left-handed materials （LHM） are investigated. The transmittance and reflectance spectra can be calculated by using the optical transmission matrix method. Comparing with the conventional Cantor multilayers, these structures with LHM have double functions of stopbands and defects. Through adjusting the thickness of dielectric layers, the properties of stopbands and defects can be obtained, respectively. For stopbands, a broad stopband filter is studied. For defect modes, multi-frequencies narrow passband filters are proposed.展开更多
文摘In this work, we derived the modal dispersion relation for TEm modes for a symmetric slab waveguide constructed from SiO2 dielectric guiding core material with lossy left-handed material (LHM) as cladding and substrate, and the power confinement factor. The dispersion relations and the power confinement factor were numerically solved for a given set of parameters: allowed frequency range;core’s thicknesses;and TEm mode order. We found that the real part of the effective refractive index decreased with thickness and frequency increase. Moreover, the imaginary part (extinction coefficient) of the effective refractive index has very small values for all thickness in the frequency ranges, which means the waveguide structure is transparent for the used frequencies. The waveguide structure offers good guiding power for all thickness in the frequency range with low power attenuation. The real part of the effective refractive index increases with the increase of mode order, and the power confinement factor decreases with the increase of mode order.
文摘为了改善单极子天线的辐射特性,通过对左手材料开路电流环谐振器(Split Ring Resonator,SRR)的结构及其电磁特性研究,提出一种新的复合天线设计思路,即将单个SRR或多个SRR与单极子天线复合。利用电磁理论和HFSS软件仿真得到工作频率为3.52GHz的这种复合天线的各项参数。仿真结果表明复合天线中SRR的个数对谐振天线的频率影响很小,其增益也基本不变。与单独的单极子天线相比,复合天线尺寸更小,类似电小天线,因此可被应用在电性能类似单极子天线,而天线尺寸又要求较小的领域。
基金Project supported by the National Natural Science Foundation of China (Grant No.61077068)the Natural Science Foundation of Shanghai Municipality (Grant No.10ZR1411900)+1 种基金the Shanghai Leading Academic Discipline Project (Grant No.S30108)the Science and Technology Commission of Shanghai Municipality (Grant No.08DZ2231100)
文摘Transmission properties of fractal Cantor distribution with left-handed materials （LHM） are investigated. The transmittance and reflectance spectra can be calculated by using the optical transmission matrix method. Comparing with the conventional Cantor multilayers, these structures with LHM have double functions of stopbands and defects. Through adjusting the thickness of dielectric layers, the properties of stopbands and defects can be obtained, respectively. For stopbands, a broad stopband filter is studied. For defect modes, multi-frequencies narrow passband filters are proposed.
