The physical expression of electrical conductivity of ternary glass can be obtained by the physical scattering theory of conducting ions by the defects in the glass. The scattering area of ion by the nucleus is given ...The physical expression of electrical conductivity of ternary glass can be obtained by the physical scattering theory of conducting ions by the defects in the glass. The scattering area of ion by the nucleus is given by the law of Rutherford in atomic physics. By this theory, the physical meaning of the microprocess of ionic conductivity of ternary glass is apparent.展开更多
Based on the quasi analytical technique, an analytical expression for the effective index profile in the depth direction in Ti:LiNbO 3 strip waveguide is theoretically derived. It is very u...Based on the quasi analytical technique, an analytical expression for the effective index profile in the depth direction in Ti:LiNbO 3 strip waveguide is theoretically derived. It is very useful for the research into the propagation characteristics of the strip waveguides with metal clad. From this expression, the field distributions and modal indices in typical waveguides are calculated. In addition, the method of how to get the position where the mode field has the maximum value is yielded in this paper. It is very important to the optical coupling between two waveguides or between the waveguide and the fiber.展开更多
An efficient and accurate method for solving the two-dimensional Helmholtz equation in domains exterior to elongated obstacles is developed in this paper.The method is based on the so called transformed field expansio...An efficient and accurate method for solving the two-dimensional Helmholtz equation in domains exterior to elongated obstacles is developed in this paper.The method is based on the so called transformed field expansion(TFE) coupled with a spectral-Galerkin solver for elliptical domain using Mathieu functions.Numerical results are presented to show the accuracy and stability of the proposed method.展开更多
文摘The physical expression of electrical conductivity of ternary glass can be obtained by the physical scattering theory of conducting ions by the defects in the glass. The scattering area of ion by the nucleus is given by the law of Rutherford in atomic physics. By this theory, the physical meaning of the microprocess of ionic conductivity of ternary glass is apparent.
文摘Based on the quasi analytical technique, an analytical expression for the effective index profile in the depth direction in Ti:LiNbO 3 strip waveguide is theoretically derived. It is very useful for the research into the propagation characteristics of the strip waveguides with metal clad. From this expression, the field distributions and modal indices in typical waveguides are calculated. In addition, the method of how to get the position where the mode field has the maximum value is yielded in this paper. It is very important to the optical coupling between two waveguides or between the waveguide and the fiber.
基金supported in part by NSF grant DMS-0610646supported by AcRF Tier 1 Grant RG58/08+1 种基金Singapore MOE Grant T207B2202Singapore NRF2007IDM-IDM002-010
文摘An efficient and accurate method for solving the two-dimensional Helmholtz equation in domains exterior to elongated obstacles is developed in this paper.The method is based on the so called transformed field expansion(TFE) coupled with a spectral-Galerkin solver for elliptical domain using Mathieu functions.Numerical results are presented to show the accuracy and stability of the proposed method.
