Using the Finite Difference Time Domain Method as a Design Tool,

The finite-difference time-domain FDTD method has been shown in the last several years to be applicable to guided-wave photonics problems. The application of the method to diffraction gratings, intersecting and bending waveguides and Bragg mirrors has served to demonstrate that method can solve a set of problems not tractable for more traditional techniques such as the beam propagation method. Although these papers have served to demonstrate the applicability of the FDTD technique, few papers have described the use of the FDTD analysis in a design environment. This paper will describe the use of the FDTD method in two design problems and show how specific engineering questions can be answered with the simulation technique. The first problem, a distributed feedback reflector for a graded index wave-guide laser, will demonstrate the ability of FDTD to model complex structures whose analysis would otherwise be virtually intractable. The second example, a multi-layer Bragg wave guide design, will show how the FDTD technique can be used to complement and extend other analysis methods.