Title :
The effect of barrier composition on the vertical carrier transport and lasing properties of 1.55-/spl mu/m multiple quantum-well structures
Author :
Akram, Muhammad Nadeem ; Kjebon, Olle ; Marcinkevicius, Saulius ; Schatz, Richard ; Berggren, Jesper ; Olsson, Fredrik ; Lourdudoss, Sebastian
Author_Institution :
Dept. of Microelectron. & Appl. Phys., R. Inst. of Technol., Stockholm
fDate :
7/1/2006 12:00:00 AM
Abstract :
In this paper, the effect of barrier bandgap and composition on the optical performance of 1.55-mum InGaAsP/InGaAsP and InGaAsP/InGaAlAs multiple quantum-well structures and Fabry-Perot lasers is evaluated experimentally. Direct vertical carrier transport measurements were performed through strain-compensated multiple quantum-well (MQW) test structures using femto-second laser pulse excitation and time-resolved photoluminescence up-conversion method. MQW test structures were grown with different barrier composition (InGaAsP and InGaAlAs) and barrier bandgap (varied from lambdag= 1440 to 1260 nm) having different conduction band DeltaEc and valence band discontinuity DeltaEv, while keeping the same InGaAsP well composition for all the structures. The ambipolar carrier transport was found to be faster in the structures with lower valence band discontinuity DeltaEv. Regrown semi-insulating buried heterostructure Fabry-Perot (SIBH-FP) lasers were fabricated from similar QWs and their static light-current-voltage characteristics (including optical gain and chirp spectra below threshold) and thermal characteristics were measured. Lasers with InGaAlAs barrier showed improved high-temperature operation, higher optical gain, higher differential gain, and lower chirp, making them suitable candidates for high-bandwidth directly modulated uncooled laser applications
Keywords :
III-V semiconductors; aluminium compounds; chirp modulation; conduction bands; energy gap; gallium arsenide; gallium compounds; high-speed optical techniques; indium compounds; optical frequency conversion; optical modulation; photoluminescence; quantum well lasers; thermo-optical effects; time resolved spectra; valence bands; 1.55 mum; Fabry-Perot lasers; InGaAsP; InGaAsP-InGaAlAs; ambipolar carrier transport; barrier bandgap; barrier composition; buried heterostructure lasers; chirp spectra; conduction band; differential gain; directly modulated laser applications; femtosecond laser pulse excitation; high-bandwidth laser applications; high-temperature operation; lasing properties; multiple quantum-well structures; optical gain; photoluminescence upconversion; semiinsulating lasers; static light-current-voltage characteristics; strain compensation; thermal characteristics; time-resolved photoluminescence; uncooled laser applications; valence band discontinuity; vertical carrier transport; vertical carrier transport measurements; Chirp; Fabry-Perot; Optical modulation; Performance evaluation; Photonic band gap; Pulse measurements; Quantum well devices; Quantum well lasers; Testing; Ultrafast optics; Carrier transport; Fabry–Perot laser; InGaAlAs; InGaAsP; quantum well (QW); time-resolved photo luminescence;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2006.876710
