The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	A theoretical study of the semiconductor laser structures with lateral discontinuity in the optical cavity
Author:	Cai, Yi
View Online:	njit-etd1994-067 (x, 98 pages ~ 3.0 MB pdf)
Department:	Department of Physics
Degree:	Master of Science
Program:	Applied Physics
Document Type:	Thesis
Advisory Committee:	Chin, Ken K. (Committee chair) Hensel, John Charles (Committee member) Yan, Yuan (Committee member)
Date:	1994-01
Keywords:	Semiconductors--Optical properties. Lasers.
Availability:	Unrestricted
Abstract:	A theoretical study of the semiconductor laser structures with lateral discontinuity in the optical resonant cavity is presented in this thesis. Specifically, the lateral discontinuity is referred to the lateral expansion structure newly invented for increasing the power output of semiconductor lasers while keeping single mode operation. In the first part of the thesis (Chapter 2 and Chapter 3), an explicit expression for calculating the lateral discontinuity problems is formulated by the incorporation of mode-matching method. Our approach is based on the mode expansion theory developed for lossless micro-wave and optical fiber waveguides, but the effect of gain in active laser media is discussed. Direct numerical evaluation to various discontinuities problems in semiconductor laser stripes are feasible, as long as the discontinuity lies entirely in a surface perpendicular to the direction of propagation. The second part of the thesis is devoted to applications of the theoretical approach. A computer program written in Fortran-5.0 is used to calculate the efficiency of lateral expansion laser structure. Graphs of the electric field patterns are produced by a program written in programming language C.