在光波导理论中,求解波导色散曲线的常用数值方法之一是效折射率法,本文给出了有效折射率求解思路,并给出了具体的matlab程序,可供学习集成光学的学生参考使用。

xTE_DispesionFun.m函数文件：

function aTE= xTE_DispersionFun(NTEe,NTMx, m)

lambda = 1.55e-6;

k0 = 2*pi/lambda;

[n3TE, n5TE] = deal(1.5100);

aTE = 1e6*(m*pi + atan(sqrt((NTEe.^2 - n3TE^2)./(NTMx^2 - NTEe.^2))) + ...

atan(sqrt((NTEe.^2 - n5TE^2)./(NTMx^2 - NTEe.^2)))) ...

./(k0*sqrt(NTMx^2 - NTEe.^2));

xTM_DispesionFun.m函数文件：

function aTM= xTM_DispersionFun(NTMe, NTEx, m)

lambda = 1.55e-6;

k0 = 2*pi/lambda;

[n3TM, n5TM] = deal(1.5095);

aTM = 1e6*(m*pi + atan(sqrt((NTEx^2*(NTMe.^2 - n3TM^2))./(n3TM^2*(NTEx^2 - NTMe.^2)))) + ...

atan(sqrt((NTEx^2*(NTMe.^2 - n5TM^2))./(n5TM^2*(NTEx^2 - NTMe.^2)))))...

./(k0*sqrt(NTEx^2 - NTMe.^2));