The influence of quantum-well composition on the performance of quantum dot lasers using InAs-InGaAs dots-in-a-well (DWELL) structures

The optical performance of quantum dot lasers with different dots-in-a-well (DWELL) structures is studied as a function of the well number and the indium composition in the InGaAs quantum well (QW) surrounding the dots. While keeping the InAs quantum dot density nearly constant, the internal quantum efficiency /spl eta//sub i/, modal gain, and characteristic temperature of 1-DWELL and 3-DWELL lasers with QW indium compositions from 10 to 20% are analyzed. Comparisons between the DWELL lasers and a conventional In/sub 0.15/Ga/sub 0.85/As strained QW laser are also made. A threshold current density as low as 16 A/cm/sup 2/ is achieved in a 1-DWELL laser, whereas the QW device has a threshold 7.5 times larger. It is found that /spl eta//sub i/ and the modal gain of the DWELL structure are significantly influenced by the quantum-well depth and the number of DWELL layers. The characteristic temperature T/sub 0/ and the maximum modal gain of the ground-state of the DWELL structure are found to improve with increasing indium in the QW It is inferred from the results that the QW around the dots is necessary to improve the DWELL laser's /spl eta//sub i/ for the dot densities studied.

[1]  Amnon Yariv,et al.  QUANTUM WELL LASERS , 1985 .

[2]  Jasprit Singh,et al.  Nonequilibrium distribution in quantum dots lasers and influence on laser spectral output , 1999 .

[3]  N. Ledentsov,et al.  Gain and differential gain of single layer InAs/GaAs quantum dot injection lasers , 1996 .

[4]  Dieter Bimberg,et al.  Gain and Threshold of Quantum Dot Lasers: Theory and Comparison to Experiments , 1997 .

[5]  George W. Turner,et al.  Ultralow-threshold (50 A/cm2) strained single-quantum-well GaInAsSb/AlGaAsSb lasers emitting at 2.05 μm , 1998 .

[6]  S. Mikhrin,et al.  Continuous-wave operation of long-wavelength quantum-dot diode laser on a GaAs substrate , 1999, IEEE Photonics Technology Letters.

[7]  A. Stintz,et al.  Tunable grating-coupled laser oscillation and spectral hole burning in an InAs quantum-dot laser diode , 2000, IEEE Journal of Quantum Electronics.

[8]  Andreas Stintz,et al.  Extremely low room-temperature threshold current density diode lasers using InAs dots in In/sub 0.15/Ga/sub 0.85/As quantum well , 1999 .

[9]  A. R. Kovsh,et al.  Photo-and electroluminescence in the 1.3-µm wavelength range from quantum-dot structures grown on GaAs substrates , 1999 .

[10]  Nikolai N. Ledentsov,et al.  Gain characteristics of quantum dot injection lasers , 1999 .

[11]  M. Sugawara,et al.  Suppression of temperature sensitivity of interband emission energy in 1.3-μm-region by an InGaAs overgrowth on self-assembled InGaAs/GaAs quantum dots , 1999 .

[12]  A. Stintz,et al.  150-nm tuning range in a grating-coupled external cavity quantum-dot laser , 2000, IEEE Photonics Technology Letters.

[13]  A. Stintz,et al.  Optical characteristics of 1.24-μm InAs quantum-dot laser diodes , 1999, IEEE Photonics Technology Letters.

[14]  D. Deppe,et al.  1.3 μm room-temperature GaAs-based quantum-dot laser , 1998 .

[15]  M. Asada,et al.  Gain and the threshold of three-dimensional quantum-box lasers , 1986 .

[16]  Nikolai N. Ledentsov,et al.  1.3 [micro sign]m GaAs-based laser using quantum dots obtained by activated spinodal decomposition , 1999 .

[17]  Govind P. Agrawal,et al.  Spatio-temporal characteristics of filamentation in broad-area semiconductor lasers , 1997 .

[18]  A. Stintz,et al.  Gain and linewidth enhancement factor in InAs quantum-dot laser diodes , 1999, IEEE Photonics Technology Letters.

[19]  Kerry J. Vahala,et al.  Quantum box fabrication tolerance and size limits in semiconductors and their effect on optical gain , 1988 .

[20]  N. Yokoyama,et al.  1.3-μm CW lasing of InGaAs-GaAs quantum dots at room temperature with a threshold current of 8 mA , 1999, IEEE Photonics Technology Letters.

[21]  Andreas Stintz,et al.  Characterization of InAs quantum dots in strained InxGa1-xAs quantum wells , 2000 .

[22]  D. Deppe,et al.  Low-threshold oxide-confined 1.3-μm quantum-dot laser , 2000, IEEE Photonics Technology Letters.

[23]  J. Chyi,et al.  Matrix dependence of strain-induced wavelength shift in self-assembled InAs quantum-dot heterostructures , 2000 .

[24]  K. Nishi,et al.  A narrow photoluminescence linewidth of 21 meV at 1.35 μm from strain-reduced InAs quantum dots covered by In0.2Ga0.8As grown on GaAs substrates , 1999 .

[25]  D. Bimberg,et al.  Theory of Quantum Dot Laser Gain and Threshold: Correlated versus Uncorrelated Electron and Hole Capture , 1997 .