Three-section semiconductor lasers are studied based on the ray method. An analytic expression of output power for the three-section semiconductor laser is derived. From this expression, threshold condition is also obtained. The relation between three-electrode semiconductor lasers and two-electrode semiconductor lasers is discussed.
"Using ray method to study three-electrode semiconductor lasers", Proc. SPIE 3547, Semiconductor Lasers III, (19 August 1998); doi: 10.1117/12.319627; https://doi.org/10.1117/12.319627