A hybrid technique is developed for the evaluation of two dimensional electromagnetic scattering from electrically large conducting bodies with cracks on their surfaces (TE case). The edge based finite element metho...A hybrid technique is developed for the evaluation of two dimensional electromagnetic scattering from electrically large conducting bodies with cracks on their surfaces (TE case). The edge based finite element method (FEM) is employed to compute the scattering from the cracks. Physical optics (PO) and physical theory of diffraction (PTD) are utilized to evaluate the scattering from the large bodies with the cracks filled with perfect conductors. These two methods are combined by an efficient coupling scheme. Some of numerical results are presented. It is shown that the hybrid technique has some advantages over other methods in regard to saving computer memory units and CPU time.展开更多
Sb2O3 doped ZnO thin film was prepared by RF magnetron sputtering technique.The influence of Sb2O3 on the structure and the optical absorption of ZnO thin film was studied by XPS,XRD apparatuses and UV-Vis spectrophot...Sb2O3 doped ZnO thin film was prepared by RF magnetron sputtering technique.The influence of Sb2O3 on the structure and the optical absorption of ZnO thin film was studied by XPS,XRD apparatuses and UV-Vis spectrophotometer.The results show that doped Sb2O3 has affected atomic and electronic structures,growth modes of crystal grains and optical absorption of ZnO.The element Sb exists in many forms in the film including transpositional atoms and compounds such as Sb2O3,Zn7Sb2O 14 etc.ZnO crystal grains grow in mixing directions.The lattice relaxation and the content of second phases increase when more Sb is doped.The UVA absorption of doped ZnO thin film increases obviously.The ultraviolet absorption peak narrows,absorption intensity increases,the absorption margin becomes steep and moves to shorter wavelength of about 5 nm,and the visible absorption increases in some sort.展开更多
The scattering of plane time-harmonic electromagnetic waves propagating in a homogeneous chiral environment by a perfectly conducting grating is studied.The problem is simplified to a two-dimensional scattering proble...The scattering of plane time-harmonic electromagnetic waves propagating in a homogeneous chiral environment by a perfectly conducting grating is studied.The problem is simplified to a two-dimensional scattering problem,and the existence and uniqueness of solutions are discussed by an integral equation approach.展开更多
Mueller matrix elements are presented represen ting scatter to 90° from an incident polarized laser beam. The cases considered include five particle sizes (such as l.24 μm, 0.494 μm, 0.36 μm, 0.123 μm, and 0....Mueller matrix elements are presented represen ting scatter to 90° from an incident polarized laser beam. The cases considered include five particle sizes (such as l.24 μm, 0.494 μm, 0.36 μm, 0.123 μm, and 0.065 μm), two concentr ations (such as 0.002 5% and 0.005% by volume), and three detector depths (such as 0, l.5 cm, and 3 cm into the scat tering volume). If the magnitudes of the elements can be rounded off to the near est 0.01, a particle size dependence is described by the resulting average mat rices, which is only two matrices for d >0.22 μm and d <0.22 μm which are nonsingular and asymmetric, respectively.展开更多
A theoretical model is proposed in order to study the configuration resonance in s-SNOM. The electromagnetic coupling between the sample and the probe tip is described with the quasi-electrostatic field theory. This m...A theoretical model is proposed in order to study the configuration resonance in s-SNOM. The electromagnetic coupling between the sample and the probe tip is described with the quasi-electrostatic field theory. This method permits us to analyze the confignrational resonance evoked by the interaction between the probe tip and the sample in s-SNOM intuitively. The resonant conditions for a certain system are presented in an explicit form. On the condition of considering the actual size of the sample dipoles and the probe dipole, we discuss the possibility of realizing the configurational resonance for various material samples. The numerical results indicate that the polarizability of the dielectric probe tip is too small to arouse this resonance, whereas, with the surface plasmon resonance emerging on the metallic nanoparticles, the enhanced polarizability of the metallic probe tip ensures the requirements of fulfilling the resonance.展开更多
This paper rerports a related microwave diagnostic methhod that measures both the electron number density and the electron-neu- tral collision frequency, which are crucial to understand the behavior of microwave trave...This paper rerports a related microwave diagnostic methhod that measures both the electron number density and the electron-neu- tral collision frequency, which are crucial to understand the behavior of microwave traveling in plasma. Arrays of standard commercial fluoresoent lamp placed directly against each other in two rows are used to produce a plasma layer. Attenuations of microwave by plasma layer are studied experimentally in the frequencies of 1--8 C44z using a synthesized signal generator and a spectnnn analyzer. Two wavepolarizations are trader investigation： dectric field of the wave is either parallel （ E -wave） or perpendicular （H-wave） to the fluorescent lamp axis. The electron number density and the electron-neutral collision frequency of fluorescent lamp plasma are obtained by microwave diagnostics, for the purpose of analyzing microwave scattering characteristics by plasma.展开更多
文摘A hybrid technique is developed for the evaluation of two dimensional electromagnetic scattering from electrically large conducting bodies with cracks on their surfaces (TE case). The edge based finite element method (FEM) is employed to compute the scattering from the cracks. Physical optics (PO) and physical theory of diffraction (PTD) are utilized to evaluate the scattering from the large bodies with the cracks filled with perfect conductors. These two methods are combined by an efficient coupling scheme. Some of numerical results are presented. It is shown that the hybrid technique has some advantages over other methods in regard to saving computer memory units and CPU time.
文摘Sb2O3 doped ZnO thin film was prepared by RF magnetron sputtering technique.The influence of Sb2O3 on the structure and the optical absorption of ZnO thin film was studied by XPS,XRD apparatuses and UV-Vis spectrophotometer.The results show that doped Sb2O3 has affected atomic and electronic structures,growth modes of crystal grains and optical absorption of ZnO.The element Sb exists in many forms in the film including transpositional atoms and compounds such as Sb2O3,Zn7Sb2O 14 etc.ZnO crystal grains grow in mixing directions.The lattice relaxation and the content of second phases increase when more Sb is doped.The UVA absorption of doped ZnO thin film increases obviously.The ultraviolet absorption peak narrows,absorption intensity increases,the absorption margin becomes steep and moves to shorter wavelength of about 5 nm,and the visible absorption increases in some sort.
文摘The scattering of plane time-harmonic electromagnetic waves propagating in a homogeneous chiral environment by a perfectly conducting grating is studied.The problem is simplified to a two-dimensional scattering problem,and the existence and uniqueness of solutions are discussed by an integral equation approach.
文摘Mueller matrix elements are presented represen ting scatter to 90° from an incident polarized laser beam. The cases considered include five particle sizes (such as l.24 μm, 0.494 μm, 0.36 μm, 0.123 μm, and 0.065 μm), two concentr ations (such as 0.002 5% and 0.005% by volume), and three detector depths (such as 0, l.5 cm, and 3 cm into the scat tering volume). If the magnitudes of the elements can be rounded off to the near est 0.01, a particle size dependence is described by the resulting average mat rices, which is only two matrices for d >0.22 μm and d <0.22 μm which are nonsingular and asymmetric, respectively.
基金This work was supported by the National Natural Science Founda-tion of China under grants No. 30170276.
文摘A theoretical model is proposed in order to study the configuration resonance in s-SNOM. The electromagnetic coupling between the sample and the probe tip is described with the quasi-electrostatic field theory. This method permits us to analyze the confignrational resonance evoked by the interaction between the probe tip and the sample in s-SNOM intuitively. The resonant conditions for a certain system are presented in an explicit form. On the condition of considering the actual size of the sample dipoles and the probe dipole, we discuss the possibility of realizing the configurational resonance for various material samples. The numerical results indicate that the polarizability of the dielectric probe tip is too small to arouse this resonance, whereas, with the surface plasmon resonance emerging on the metallic nanoparticles, the enhanced polarizability of the metallic probe tip ensures the requirements of fulfilling the resonance.
文摘This paper rerports a related microwave diagnostic methhod that measures both the electron number density and the electron-neu- tral collision frequency, which are crucial to understand the behavior of microwave traveling in plasma. Arrays of standard commercial fluoresoent lamp placed directly against each other in two rows are used to produce a plasma layer. Attenuations of microwave by plasma layer are studied experimentally in the frequencies of 1--8 C44z using a synthesized signal generator and a spectnnn analyzer. Two wavepolarizations are trader investigation： dectric field of the wave is either parallel （ E -wave） or perpendicular （H-wave） to the fluorescent lamp axis. The electron number density and the electron-neutral collision frequency of fluorescent lamp plasma are obtained by microwave diagnostics, for the purpose of analyzing microwave scattering characteristics by plasma.
