SOLUTION TO THE WAVE-EQUATION IN THE NUMERICAL-SIMULATION OF BURIED HETEROSTRUCTURE LASERS

In the numerical simulation of buried heterostructure (BH) lasers a fast, accurate method is essential to solve the wave equation. The paper compares the effective index method with the weighted index method and it is found that if modes other than the fundamental are to be considered the effective index method becomes inaccurate. The authors investigate several methods for solving the algebraic eigenvalue equation which results from the effective and weighted index methods. It is found that a method based on inverse iteration with successive eigenvalue refinement is highly efficient, with good initial approximations to the eigenvalue and eigenvector obtained using a Sturm sequence and inversion.