Modeling first-order distributed feedback semiconductor lasers at NIR

This work demonstrates the modeling process of calculating coupling coefficients of first-order distributed feedback (DFB) semiconductor lasers, operating on transverse electric modes in the near-infrared (NIR) spectrum range. Optical waveguides are common structures in semiconductor lasers. The structure has dielectric layers and a metal grating layer. The interface between the metal layer and its neighboring dielectric layer has a sinusoidal corrugated geometry. Coupling coefficients are important parameters when analyzing laser performance. To calculate the coupling coefficient of a shiny-metal-grating waveguide, an electromagnetic model is constructed by truncated Floquet-Bloch formalism (TFBF). Ray optics technique is also used to calculate the coupling coefficients. These two methods have close results.