Growth and optimization of 2-μm InGaSb/AlGaSb quantum-well-based VECSELs on GaAs/AlGaAs DBRs

Pankaj Ahirwar, Thomas J. Rotter, Darryl Shima, Nahid A. Jahan, Stephen P.R. Clark, Sadhvikas J. Addamane, Ganesh Balakrishnan, Alexandre Laurain, Jörg Hader, Yi Ying Lai, Jerome V. Moloney, Ikuo Suemune, Robert G. Bedford

Research output: Contribution to journalArticlepeer-review

6 Scopus citations


We report the growth of optically pumped vertical-external-cavity surface-emitting lasers (VECSELs) based on InGaSb/AlGaSb quantum wells grown on GaAs/AlGaAs distri-buted Bragg reflectors (DBRs). The 7.78% lattice mismatch between GaSb and GaAs is accommodated by an array of 90° misfit dislocations at the interface. This results in spontaneous relaxation of the GaSb epilayer and also significantly reduces the threading dislocation density. The VECSELs are operated in both pulsed (with 340-W peak output power) and continuous wave mode (with 0.12-W peak output power). We investigate the effects of the GaSb/GaAs interface by comparing the lattice mismatched III-Sb VECSEL grown on GaAs/AlGaAs DBRs to a lattice matched III-Sb VECSEL grown on GaSb/AlAsSb DBRs. The lattice matched VECSEL outperforms the lattice mismatched VECSEL in terms of threshold pump density, efficiency, and maximum continuous-wave output power. This can be attributed to the presence of threading dislocations throughout the active region of the mismatched VECSEL, which is confirmed by cross-sectional transmission electron microscopy. The optical properties of the III-Sb active regions are characterized by time-resolved photoluminescence, which can be used to optimize the IMF interface.

Original languageEnglish (US)
Article number6410324
JournalIEEE Journal on Selected Topics in Quantum Electronics
Issue number4
StatePublished - 2013


  • Semiconductor lasers
  • quantum-well lasers
  • surface-emitting lasers

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Growth and optimization of 2-μm InGaSb/AlGaSb quantum-well-based VECSELs on GaAs/AlGaAs DBRs'. Together they form a unique fingerprint.

Cite this