摘要
从亥姆霍兹方程出发,得到了各向异性光波导在弱导近似下的耦合模理论。耦合系数包括偏振耦合项和双折射耦合项。并用马卡提里近似下的模式作为零级近似。用一级微扰法计算了折射率渐变分布的钛扩散铌酸锂矩形波导的传播常数。在给定参数的情况下,得到双折射项引起的传播常数的改变约为主微扰项的3%,因此双折射耦合对钛扩散铌酸锂矩形波导的性能影响不可忽略,这对设计和分析与它相关的光波导器件具有指导意义。
A new coupled-mode theory based on scalar modes is presented for the anisotropic waveguide with random disturbance via Helmholtz equation and a modified dielectric tensor. The polarization coupling term and birefringence coupling term are included in the coupling coefficient expression. In addition, the numerical modeling of the propagation is made constant for the Ti： LiNbO3 with the Marcatili＇s approximation and the first-order perturbation. It is found that the change of the propagation constant due to birefringence coupling is about as three percent as that due to the main perturbation term, which shows that the birefringence can not be neglected for the Ti： LiNbO3 rectangle waveguide. The work has a guidance to the study of the optical waveguide devices with the Ti： LiNbO3 waveguide.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2006年第10期1702-1706,共5页
High Power Laser and Particle Beams
基金
重庆市科委基金资助课题(2005BB4070)
重庆市教委基金资助课题(050502)
重庆邮电学院青年基金资助课题(A2005-17)
关键词
导波光学
钛扩散铌酸锂矩形波导
双折射耦合
传播常数
Waveguide optics
Ti：LiNbO3 rectangle waveguide
Birefringence coupling
Propagation constant
