Dresden 2006 – wissenschaftliches Programm

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HL: Halbleiterphysik

HL 22: Semiconductor laser II

HL 22.4: Vortrag

Dienstag, 28. März 2006, 16:00–16:15, BEY 154

Influence of electrostatic confinement on optical gain in GaInNAs quantum well lasers — •Sorcha Healy and Eoin OReilly — Tyndall National Institute, Lee Maltings, Cork, Ireland

There remains controversy surrounding the cause of the magnitude and temperature sensitivity of the threshold current density of 1.3 µm GaInNAs quantum well (QW) lasers, with several authors attributing the strong temperature sensitivity to hole leakage, due to the relatively low valence band offset in GaInNAs/GaAs QW structures. We use a Poisson solver along with a 10-band k.p Hamiltonian to calculate self-consistently the influence of electrostatic confinement on the optical gain in such lasers. We find that the proper inclusion of such effects significantly reduces the hole leakage effect, with the electrostatic attraction of the electrons significantly increasing the binding of heavy holes in the QW region. We conclude by comparison with previous theoretical and experimental studies that the room temperature threshold current is generally dominated by monomolecular recombination, while the temperature sensitivity is due predominantly to Auger recombination.