Improved finitedifference vector beam propagation formulation for gradedindex waveguides
Abstract
An improved finitedifference vector beam propagation formulation for gradedindex waveguides is presented. The modification over the existing version involves a more accurate representation of the Fresnel operator in finitedifference form that accounts for the gradient of the refractive index in the vector Helmholtz equation. The modified scheme is assessed by calculating the TM mode propagation constants of singlemode planar guides that yield better agreement to the exact values over the existing scheme. Furthermore, the calculated coupling lengths of a vertical directional coupler show improved comparison to experimental data.
 Publication:

IEEE Photonics Technology Letters
 Pub Date:
 April 1994
 DOI:
 10.1109/68.281821
 Bibcode:
 1994IPTL....6..543Y
 Keywords:

 Fiber Optics;
 Finite Difference Theory;
 Gradient Index Optics;
 Light Transmission;
 Optical Waveguides;
 Refractivity;
 Fast Fourier Transformations;
 Helmholtz Equations;
 Mathematical Models;
 Optical Coupling;
 Communications and Radar