A quantitative study of radiative, Auger, and defect related recombination processes in 1.3-μm GaInNAs-based quantum-well lasers

• Published in: IEEE journal of selected topics in quantum electronics 2002-07, Vol.8 (4), p.801-810
• Main Authors: Fehse, R., Tomic, S., Adams, A.R., Sweeney, S.J., O'Reilly, E.P., Andreev, A., Riechert, H.
• Format: Article
• Language: English
• Subjects: Augers; Density; Devices; Lasers; Mathematical analysis; Quantum wells; Threshold currents; Thresholds
• ISSN: 1077-260X
• DOI: 10.1109/JSTQE.2002.801684

By measuring the spontaneous emission (SE) from normally operating similar to 1.3- mu m GaInNAs-GaAs-based lasers we have quantitatively determined the variation of each of the current paths present in the devices as a function of temperature from 130 K to 370 K. From the SE measurements we determine how the current I close to threshold, varies as a function of carrier density n, which enables us to separate out the main current paths corresponding to monomolecular (defect-related), radiative or Auger recombination. We find that defect-related recombination forms similar to 55% of the threshold current at room temperature (RT). At RT, radiative recombination accounts for similar to 20% of I sub(th) with the remaining similar to 25% being due to nonradiative Auger recombination. Theoretical calculations of the threshold carrier, density as a function of temperature were also performed, using a ten-band k . p Hamiltonian. Together with the experimentally determined defect-related, radiative, and Auger currents we deduce the temperature variation of the respective recombination coefficients (A, B, and C). These are compared with theoretical calculations of the coefficients and good agreement is obtained. Our results suggest that by eliminating the dominant defect-related current path, the threshold current density of these GaInNAs-GaAs-based devices would be approximately halved at RT. Such devices could then have threshold current densities comparable with the best InGaAsP/InP-based lasers with the added advantages provided by the GaAs system that are important for vertical integration.