This appendix gives a systematic approach to providing a program for solving propagation, confinement factor and far-field emission when electromagnetic waves are guided by slab waveguides. Almost arbitrary numbers of layers can be computed with complex refractive indices. Here, by examining a five-layer system, the way forward to a semi-automated method for an arbitrary number of layers with complex refractive indices is demon strated. Multilayer guides are particularly relevant in discussing DFB lasers where the longitudinally periodic profile of the permittivity has lateral variations across the waveguide which can be taken into account by having a series of layers with different patterns of permittivity, giving an average permittivity and an average periodic component which can be calculated using the programs.

Inspec keywords: light propagation; semiconductor lasers; distributed feedback lasers; waveguide lasers; refractive index; optical multilayers; permittivity; laser beams

Other keywords: five-layer system; multilayer slab guide; confinement factor; longitudinally periodic profile; complex refractive indices; electromagnetic wave propagation; far-field emission; permittivity; DFB lasers; semiautomated method

Subjects: Laser beam characteristics and interactions