Title :
Non-Markovian gain of strained-layer wurtzite GaN quantum-well lasers with many-body effects
Author :
Ahn, Doyeol David ; Park, S.-H. ; Kim, T.I.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of Seoul, South Korea
Abstract :
A theoretical model for the optical gain of strained-layer wurtzite GaN quantum-well (QW) lasers is developed taking into account valence-band mixing, many-body effects and non-Markovian relaxation. The valence-band structure is calculated from a 6×6 multiband effective mass Hamiltonian for the wurtzite structure taking into account built-in strain due to lattice mismatch. The theoretical foundation for the optical processes is based on the time-convolutionless reduced-density operator formalism given in previous papers for an arbitrary driven system coupled to a stochastic reservoir. Many-body effects are taken into account within the time-dependent Hartree-Fock approximation and the optical gain with Coulomb (or excitonic) enhancement is derived by integrating the equation of motion for the interband polarization. It is predicted that the Coulomb enhancement of gain is pronounced with increasing magnitude of compressive strain in the QW
Keywords :
HF calculations; III-V semiconductors; effective mass; gallium compounds; many-body problems; quantum well lasers; semiconductor device models; stochastic systems; valence bands; 6×6 multiband effective mass Hamiltonian; Coulomb enhancement; Coulomb excitonic enhancement; GaN; GaN QW lasers; built-in strain; compressive strain; equation of motion; increasing magnitude; interband polarization; lattice mismatch; many-body effects; non-Markovian gain; non-Markovian relaxation; optical gain; optical processes; stochastic reservoir; strained-layer wurtzite GaN quantum-well lasers; theoretical foundation; theoretical model; time-convolutionless reduced-density operator formalism; time-dependent Hartree-Fock approximation; valence-band mixing; valence-band structure; wurtzite structure; Capacitive sensors; Effective mass; Gallium nitride; Laser modes; Laser theory; Lattices; Optical coupling; Optical mixing; Quantum well lasers; Quantum wells;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/2944.704112
