Mode matching method is used to analyze the scattering characteristics of thecircular-to-circular groove waveguide junction. Matching the electric fields and magnetic fields atthe boundary of the junction, and multipl...Mode matching method is used to analyze the scattering characteristics of thecircular-to-circular groove waveguide junction. Matching the electric fields and magnetic fields atthe boundary of the junction, and multiplying the mode functions of the circular waveguide andcircular groove waveguide on both sides of the boundary equation, the scattering matrix equation isobtained, the scattering coefficients can be obtained from the equation. Then the scatteringcharacteristics of the iris with circular window in circular groove waveguide are analyzed. At lastthe convergent problem is discussed; when choosing a suitable mode group, convergent numericalresults are obtained, and the frequency response of the iris' scattering coefficients is also given.展开更多
Circular dichroism(CD)has shown very interesting possibilities as a means to characterize the chiral signal of a chiral structure.Here,we theoretically demonstrated enhanced and tunable CD in the visible light regime ...Circular dichroism(CD)has shown very interesting possibilities as a means to characterize the chiral signal of a chiral structure.Here,we theoretically demonstrated enhanced and tunable CD in the visible light regime using a composite structure consisting of a double-layer metal grating gaped by a dielectric waveguide layer.Based on the coupling of the waveguide modes and the localized plasmonic resonances,the CD could reach a maximum value as high as 0.52 at635 nm,which is four times higher than the CD value obtained in a conventional double-layer grating without the waveguide coupling effect.Furthermore,the spectral positions of the enhanced CD bands could be easily tuned by controlling the structural parameters.The proposed hybrid double-grating and waveguide structures could have potential applications in chiral selective imaging,sensing and spectroscopy,especially where the transmission measurement is required.展开更多
The dispersion characteristics of a circular dielectric waveguide with periodic metal-lic strips are analyzed by the Galerkin’s method.After obtaining the rigorous dispersion equation,the dispersion curves for both T...The dispersion characteristics of a circular dielectric waveguide with periodic metal-lic strips are analyzed by the Galerkin’s method.After obtaining the rigorous dispersion equation,the dispersion curves for both TE<sub>01</sub>and TM<sub>01</sub>modes are calculated by the improved Newton’smethod.The variations of the normalized center frequency,width and maximum attenuation con-stant of the stopband with the normalized width of the metallic strips are given.The convergenceproperties of numerical solutions are also discussed.On the basis of the analysis,some usefulguidelines for filter design are thereby suggested.展开更多
Based on the method of separating variables and the technique of Muller’s calculating roots, the propagation characteristics of hybrid modes in homogeneous and inhomogeneous circular Faraday chirowaveguides are exami...Based on the method of separating variables and the technique of Muller’s calculating roots, the propagation characteristics of hybrid modes in homogeneous and inhomogeneous circular Faraday chirowaveguides are examined in detail. Numerical results are presented to demonstrate the combined effects of different constitutive parameters on the mode bifurcation, symmetry and nonreciprocity, backward-wave and attenuation of hybrid modes, which are different from the cases of ordinary gyrotropic and reciprocal chiral waveguides.展开更多
By investigating the interaction of an n-type silicon sample with the TM01 mode millimeter wave in a circular waveguide, a viable high-power TM01 millimeter wave sensor is proposed. Based on the hot electron effect, t...By investigating the interaction of an n-type silicon sample with the TM01 mode millimeter wave in a circular waveguide, a viable high-power TM01 millimeter wave sensor is proposed. Based on the hot electron effect, the silicon sample serving as a sensing element（SE） and appropriately mounted on the inner wall of the circular waveguide is devoted to the on-line measurement of a high-power millimeter wave pulse. A three-dimensional parallel finite-difference time-domain method is applied to simulate the wave propagation within the measuring structure. The transverse electric field distribution, the dependences of the frequency response of the voltage standing-wave ratio（VSWR） in the circular waveguide, and the average electric field amplitude within the SE on the electrophysical parameters of the SE are calculated and analyzed in the frequency range of 300–400 GHz. As a result, the optimal dimensions and specific resistance of the SE are obtained,which provide a VSWR of no more than 2.0, a relative sensitivity around 0.0046 kW-1 fluctuating within ±17.3%, and a maximum enduring power of about 4.3 MW.展开更多
This paper gives the simple and logical approach of LP modes in circular and elliptical waveguides. Earlier the basic approach of modes in circular and elliptical fibers was studied by the authors. In this paper, the ...This paper gives the simple and logical approach of LP modes in circular and elliptical waveguides. Earlier the basic approach of modes in circular and elliptical fibers was studied by the authors. In this paper, the role of radial antinode in circular and elliptical waveguides is given clearly. Splitting of modes in circular and elliptical fiber has been discussed.展开更多
The solution of Maxwell’s equations for a piecewise homogeneous medium of cylindrical symmetry has been obtained. The parameters of the cylindrical waveguide modes have been calculated on its basis. The conclusions a...The solution of Maxwell’s equations for a piecewise homogeneous medium of cylindrical symmetry has been obtained. The parameters of the cylindrical waveguide modes have been calculated on its basis. The conclusions are confirmed by numerical calculation of the first four modes of a hollow metal waveguide operating as a mode convector.展开更多
This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in bot...This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance(Z_(PV)), effective refractive index(n_(eff)) and propagation length(L_(spp)), have been obtained by using full wave simulation.展开更多
Mode matching method is used to analyze the scattering characteristics of the rectangular-to-circular groove waveguide junction. Firstly, the scattering matrix equation is obtained by matching the electromagnetic fiel...Mode matching method is used to analyze the scattering characteristics of the rectangular-to-circular groove waveguide junction. Firstly, the scattering matrix equation is obtained by matching the electromagnetic fields at the boundary of the junction. The scattering coefficients can be obtained from the equation. Secondly the scattering characteristics of the iris with rectangular window positioned in circular groove waveguide are briefly analyzed. Thirdly, the convergent problem is discussed and the numerical results are given. At last experiment is made and good agreements is found between the calculated results and the measured results.展开更多
The normal modes in overmoded plasma waveguide coated with a lossy material are analyzed, particularly for the variation of its propagation properties with plasma parameters, coating materials, dimensions of the waveg...The normal modes in overmoded plasma waveguide coated with a lossy material are analyzed, particularly for the variation of its propagation properties with plasma parameters, coating materials, dimensions of the waveguide and frequencies. The separate characteristic equations of normal modes are derived, and their relevant approximate solutions are given. The limit results are consistent with those given in literature. The analysis shows that the propagation properties of the overmoded plasma circular waveguide can be controlled by choosing proper plasma parameters, coating materials and waveguide dimensions.展开更多
文摘Mode matching method is used to analyze the scattering characteristics of thecircular-to-circular groove waveguide junction. Matching the electric fields and magnetic fields atthe boundary of the junction, and multiplying the mode functions of the circular waveguide andcircular groove waveguide on both sides of the boundary equation, the scattering matrix equation isobtained, the scattering coefficients can be obtained from the equation. Then the scatteringcharacteristics of the iris with circular window in circular groove waveguide are analyzed. At lastthe convergent problem is discussed; when choosing a suitable mode group, convergent numericalresults are obtained, and the frequency response of the iris' scattering coefficients is also given.
基金Project supported by the National Natural Science Foundation of China(Grant No.11474215)。
文摘Circular dichroism(CD)has shown very interesting possibilities as a means to characterize the chiral signal of a chiral structure.Here,we theoretically demonstrated enhanced and tunable CD in the visible light regime using a composite structure consisting of a double-layer metal grating gaped by a dielectric waveguide layer.Based on the coupling of the waveguide modes and the localized plasmonic resonances,the CD could reach a maximum value as high as 0.52 at635 nm,which is four times higher than the CD value obtained in a conventional double-layer grating without the waveguide coupling effect.Furthermore,the spectral positions of the enhanced CD bands could be easily tuned by controlling the structural parameters.The proposed hybrid double-grating and waveguide structures could have potential applications in chiral selective imaging,sensing and spectroscopy,especially where the transmission measurement is required.
基金Supported by the National Natural Science Foundation of China and the Foundation of State Education Commission.
文摘The dispersion characteristics of a circular dielectric waveguide with periodic metal-lic strips are analyzed by the Galerkin’s method.After obtaining the rigorous dispersion equation,the dispersion curves for both TE<sub>01</sub>and TM<sub>01</sub>modes are calculated by the improved Newton’smethod.The variations of the normalized center frequency,width and maximum attenuation con-stant of the stopband with the normalized width of the metallic strips are given.The convergenceproperties of numerical solutions are also discussed.On the basis of the analysis,some usefulguidelines for filter design are thereby suggested.
文摘Based on the method of separating variables and the technique of Muller’s calculating roots, the propagation characteristics of hybrid modes in homogeneous and inhomogeneous circular Faraday chirowaveguides are examined in detail. Numerical results are presented to demonstrate the combined effects of different constitutive parameters on the mode bifurcation, symmetry and nonreciprocity, backward-wave and attenuation of hybrid modes, which are different from the cases of ordinary gyrotropic and reciprocal chiral waveguides.
基金Project supported by the National Natural Science Foundation of China(Grant No.61231003)
文摘By investigating the interaction of an n-type silicon sample with the TM01 mode millimeter wave in a circular waveguide, a viable high-power TM01 millimeter wave sensor is proposed. Based on the hot electron effect, the silicon sample serving as a sensing element（SE） and appropriately mounted on the inner wall of the circular waveguide is devoted to the on-line measurement of a high-power millimeter wave pulse. A three-dimensional parallel finite-difference time-domain method is applied to simulate the wave propagation within the measuring structure. The transverse electric field distribution, the dependences of the frequency response of the voltage standing-wave ratio（VSWR） in the circular waveguide, and the average electric field amplitude within the SE on the electrophysical parameters of the SE are calculated and analyzed in the frequency range of 300–400 GHz. As a result, the optimal dimensions and specific resistance of the SE are obtained,which provide a VSWR of no more than 2.0, a relative sensitivity around 0.0046 kW-1 fluctuating within ±17.3%, and a maximum enduring power of about 4.3 MW.
文摘This paper gives the simple and logical approach of LP modes in circular and elliptical waveguides. Earlier the basic approach of modes in circular and elliptical fibers was studied by the authors. In this paper, the role of radial antinode in circular and elliptical waveguides is given clearly. Splitting of modes in circular and elliptical fiber has been discussed.
文摘The solution of Maxwell’s equations for a piecewise homogeneous medium of cylindrical symmetry has been obtained. The parameters of the cylindrical waveguide modes have been calculated on its basis. The conclusions are confirmed by numerical calculation of the first four modes of a hollow metal waveguide operating as a mode convector.
文摘This article analyzes the transmission line characteristics of plasmonic hybrid metal insulator metal(HMIM) wave-guide, circular ring resonator(CRR) based dual-band band-pass filters with two transmission poles in both pass-bands in the optical regime using coupled line feed. The transmission line characteristics of an HMIM waveguide, such as characteristic impedance(Z_(PV)), effective refractive index(n_(eff)) and propagation length(L_(spp)), have been obtained by using full wave simulation.
文摘Mode matching method is used to analyze the scattering characteristics of the rectangular-to-circular groove waveguide junction. Firstly, the scattering matrix equation is obtained by matching the electromagnetic fields at the boundary of the junction. The scattering coefficients can be obtained from the equation. Secondly the scattering characteristics of the iris with rectangular window positioned in circular groove waveguide are briefly analyzed. Thirdly, the convergent problem is discussed and the numerical results are given. At last experiment is made and good agreements is found between the calculated results and the measured results.
文摘The normal modes in overmoded plasma waveguide coated with a lossy material are analyzed, particularly for the variation of its propagation properties with plasma parameters, coating materials, dimensions of the waveguide and frequencies. The separate characteristic equations of normal modes are derived, and their relevant approximate solutions are given. The limit results are consistent with those given in literature. The analysis shows that the propagation properties of the overmoded plasma circular waveguide can be controlled by choosing proper plasma parameters, coating materials and waveguide dimensions.
