On quantum-dot lasing at gain peak with linewidth enhancement factor αH = 0

This paper describes an investigation of the linewidth enhancement factor αH in a semiconductor quantum-dot laser. Results are presented for active region parameters and laser configurations important for minimizing αH. In particular, the feasibility of lasing at the gain peak with αH = 0 is explored. The study uses a many-body theory with dephasing effects from carrier scattering treated at the level of quantum-kinetic equations. InAs quantum-dot lasers with different p-modulation doping densities are fabricated and measured to verify the calculated criteria on laser cavity design and epitaxial growth conditions.This paper describes an investigation of the linewidth enhancement factor αH in a semiconductor quantum-dot laser. Results are presented for active region parameters and laser configurations important for minimizing αH. In particular, the feasibility of lasing at the gain peak with αH = 0 is explored. The study uses a many-body theory with dephasing effects from carrier scattering treated at the level of quantum-kinetic equations. InAs quantum-dot lasers with different p-modulation doping densities are fabricated and measured to verify the calculated criteria on laser cavity design and epitaxial growth conditions.