Spectral and Transient Luminescence Measurements on GaSb/AlGaSb Quantum Wells Grown on GaSb/GaAs Heterojunctions with and without Interfacial Misfit Arrays

Jahan, Nusrat; Ahirwar, P.; Rotter, Thomas; Balakrishnan, Ganesh; Kumano, H.; Suemune, I.

doi:10.7567/jjap.52.022101

Cited by 1 publication

(3 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, the PL decay measured on the QW with IMF was spectrally separated into the two regions of 1367-1405 nm (882-907 meV) and 1406-1444 nm (859-882 meV) and integrated in each region. This spectral separation resulted in single exponential decays and the decay time constants determined in the lower and higher photon energy regions very nicely reproduced the τ 1 and τ 2 values given in Table II, respectively [23]. Therefore τ 1 and τ 2 are the decay time constants related to the QW ground states and the excited states, respectively.…”

Section: Threading Dislocation Reduction Strategiessupporting

confidence: 74%

“…16 and are summarized in Table II. To identify the origin of the two decay time constants of τ 1 and τ 2 , we have studied the time decay by spectral integrations in limited ranges [23]. For example, the PL decay measured on the QW with IMF was spectrally separated into the two regions of 1367-1405 nm (882-907 meV) and 1406-1444 nm (859-882 meV) and integrated in each region.…”

Section: > Replace This Line With Your Paper Identification Number (Dmentioning

confidence: 99%

“…[23] In Figure 15 we estimate the dislocation density N D as a function of distance from the GaSb/GaAs interface. The dislocation density reduces from ~ 10 8 cm -2 to about ~ 10 7 cm -2 at a distance of about ~ 3 µm from the interface.…”

Section: B Tem Based Analysis Of Threading Dislocation Density In Thmentioning

confidence: 99%

See 2 more Smart Citations

Growth and Optimization of 2-μm InGaSb/AlGaSb Quantum-Well-Based VECSELs on GaAs/AlGaAs DBRs

Ahirwar

Rotter

Shima

et al. 2013

IEEE J. Select. Topics Quantum Electron.

View full text Add to dashboard Cite

Abstract-We report the growth of optically pumped vertical external cavity surface emitting lasers (VECSELs) based on InGaSb/AlGaSb quantum wells grown on GaAs/AlGaAs distributed Bragg reflectors (DBRs), which are in turn grown on GaAs substrates. We attempt to mitigate the effects of the 7.78% lattice mismatch that exists between GaSb and GaAs by introducing an interfacial layer of 90º misfit dislocations (IMF) at the mismatched interface. This results in the spontaneous relaxation of the GaSb epi-layer and significantly reduces threading dislocation density. The IMF interface is optimized through the use of an antimony soak layer, which results in a distinct (2 x 8) Sb reconstructed surface on GaAs. The III-Sb VECSEL active region is optimized for various parameters including quantum well quality and the thickness of the individual layers. The VECSELs are optically pumped using both pulsed sources for sub-thermal measurements and continuous wave (CW) sources. The pulsed measurements have resulted in record results of 340 W peak power while the CW measurements have resulted in a maximum output power of 0.12 W, with both lasers emitting at 2 µm. We investigate the effects of the mismatched interface by comparing the III-Sb VECSEL grown on GaAs/AlGaAs DBRs to a lattice matched III-Sb VECSEL grown on GaSb/AlAsSb DBRs. The results indicate deterioration in the lattice-mismatched laser's performance compared to the lattice-matched laser's performance in terms of threshold pump density, efficiency and maximum CW output power. Further comparison of the structures using cross-section transmission electron microscopy also confirms the presence of threading dislocations in the III-Sb active region grown on GaAs/AlGaAs DBRs. The ability to use such mismatched active regions will therefore depend on the stability and reproducibility of the IMF interface. The optical properties of the III-SB active regions grown on the GaAs substrates using IMF technique are investigated using time-resolved photoluminescence with the objective of using this technique to optimize the IMF interface in future studies.Index Terms-Semiconductor lasers, Quantum well lasers, Surface-emitting lasers.I. INTRODUCTION he two-micron vertical external cavity surface emitting laser has applications in a variety of technologies from gas sensing to infrared counter measures. The use of antimonide semiconductors for lasers in the 1.8 -3.3 µm wavelength range is well established with a majority of such lasers fabricated as edge emitting diodes including distributed feedback (DFB) lasers.[1] However, the high beam quality and high output power of the VECSEL could be of considerable advantage to the antimonide lasers in this wavelength range.The power scaling in a VECSEL is achieved by increasing the diameter of the pump spot while keeping the pump density constant. The quantum well VECSELs based on InGaAs quantum wells grown on GaAs substrates have recently broken the 100 Watt barriers for CW output power from a single chip. [2] However, the same level of suc...

show abstract

Section: Threading Dislocation Reduction Strategiessupporting

confidence: 74%

Section: > Replace This Line With Your Paper Identification Number (Dmentioning

confidence: 99%

See 1 more Smart Citation

Growth and Optimization of 2-μm InGaSb/AlGaSb Quantum-Well-Based VECSELs on GaAs/AlGaAs DBRs

Ahirwar

Rotter

Shima

et al. 2013

IEEE J. Select. Topics Quantum Electron.

View full text Add to dashboard Cite

show abstract

Spectral and Transient Luminescence Measurements on GaSb/AlGaSb Quantum Wells Grown on GaSb/GaAs Heterojunctions with and without Interfacial Misfit Arrays

Cited by 1 publication

References 37 publications

Growth and Optimization of 2-μm InGaSb/AlGaSb Quantum-Well-Based VECSELs on GaAs/AlGaAs DBRs

Growth and Optimization of 2-μm InGaSb/AlGaSb Quantum-Well-Based VECSELs on GaAs/AlGaAs DBRs

Contact Info

Product

Resources

About