Resonant-state expansion of light propagation in nonuniform waveguides

作     者：S. V. Lobanov G. Zoriniants W. Langbein E. A. Muljarov 

作者机构：School of Physics and Astronomy Cardiff University Cardiff CF24 3AA United Kingdom 

出 版 物：《Physical Review A》 (Phys. Rev. A)

年 卷 期：2017年第95卷第5期

页      面：053848-053848页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：Cardiff University EPSRC, (EP/K503988/1) Engineering and Physical Sciences Research Council, EPSRC, (EP/M020479/1) 

主　　题：Classical optics Electromagnetism Photonics Waveguides Electromagnetic field calculations 

摘      要：A rigorous approach for precise and efficient calculation of light propagation along nonuniform waveguides is presented. Resonant states of a uniform waveguide, which satisfy outgoing-wave boundary conditions, form a natural basis for expansion of the local electromagnetic field. Using such an expansion at fixed frequency, we convert the wave equation for light propagation in a nonuniform waveguide into an ordinary second-order matrix differential equation for the expansion coefficients depending on the coordinate along the waveguide. We illustrate the method on several examples of nonuniform planar waveguides and evaluate its efficiency compared to the aperiodic Fourier modal method and the finite element method, showing improvements of one to four orders of magnitude. A similar improvement can be expected also for applications in other fields of physics showing wave phenomena, such as acoustics and quantum mechanics.