Recombination and loss mechanisms in low-threshold InAs-GaAs 1.3-/spl mu/m quantum-dot lasers

• Published in: IEEE journal of selected topics in quantum electronics Vol. 11; no. 5; pp. 1041 - 1047
• Main Authors: Marko, I.P., Adams, A.R., Sweeney, S.J., Mowbray, D.J., Skolnick, M.S., Liu, H.Y., Groom, K.M.
• Format: Journal Article
• Language: English
• Published: IEEE 01-09-2005
• Subjects: Characteristic temperature; hydrostatic high pressure; InAs; Land surface temperature; Laser theory; Photonic band gap; quantum dot (QD); Quantum dot lasers; Quantum dots; Radiative recombination; recombination mechanisms; semiconductor laser; Semiconductor lasers; Temperature distribution; Temperature sensors; Threshold current
• ISSN: 1077-260X; 1558-4542
• DOI: 10.1109/JSTQE.2005.853847

We show that even in quantum-dot (QD) lasers with very low threshold current densities (J/sub th/=40--50 A/cm/sup 2/ at 300 K), the temperature sensitivity of the threshold current arises from nonradiative recombination that comprises /spl sim/60% to 70% of J/sub th/ at 300 K, whereas the radiative part of J/sub th/ is almost temperature insensitive. The influence of the nonradiative recombination mechanism decreases with increasing hydrostatic pressure and increasing band gap, which leads to a decrease of the threshold current. We also studied, for the first time, the band gap dependence of the radiative part of J/sub th/, which in contrast increases strongly with increasing band gap. These results suggest that Auger recombination is an important intrinsic recombination mechanism for 1.3-/spl mu/m lasers, even in a very low threshold QD device, and that it is responsible for the temperature sensitivity of the threshold current.