... Electron., QE-20(3), 230–235, 1984.6. Cartledge, J. C. and Elrefaie, A. F., Threshold gain difference requirements for nearly single-longitudinal-mode lasers, J. Lightwave Technol., LT-8(5), 704–715, ... wavelength. Due to non-uniform field distribution, however, the single-mode stabilityFigure 3.13 Schematic representation of a three-phase-shift (3PS) DFB LD (after [28]). AR: anti-reflection coating.SUMMARY973.2 ... SRwere derived for purely index-coupled,mixed-coupled and purely gain-coupled structures. By assuming a zero phase differencebetween the index and the gain term, the complex coupling coefficient...