Ground state lasing at 1.30 µm from InAs/GaAs quantum dot lasers grown by metal–organic chemical vapor deposition

Abstract

We investigated the effects of post-growth annealing on the photoluminescence (PL) characteristics of InAs/GaAs quantum dots (QDs) grown by metal-organic chemical vapor deposition (MOCVD). The onset temperature at which both the peak linewidth and the PL intensity degraded and the blueshift of the ground state emission wavelength occurred was found to depend on both the QD density and the In composition of the capping layer. This behavior is particularly important in view of QD integration in photonic devices. From the knowledge of the dependences of the PL characteristics after annealing on the QD and capping growth conditions, ground state lasing at 1.30 microm could be demonstrated from InAs/GaAs QDs grown by MOCVD. Finally, we compared the laser characteristics of InAs/GaAs QDs with those of InAs/Sb:GaAs QDs, grown according to the antimony-mediated growth technique, and showed that InAs/Sb:GaAs QDs are more appropriate for laser fabrication at 1.3 microm by MOCVD.

Electroluminescence at 1.3 µm from InAs/GaAs quantum dots monolithically grown on Ge/Si substrate by metal organic chemical vapor deposition

“…The density of QDs grown on GaAs=Ge=Si substrate is almost comparable to that of QDs grown on a GaAs substrate, used for the fabrication of low-threshold-current lasers. 2) Note that the QDs are free from coalescence dots in spite of the high density, and these QDs are significantly different from the previously reported work of InAs=GaAs QDs directly grown on Ge substrates by MOCVD, which are characterized by a low density of coherent dots and a high density of coalescence dots. 22) The SRL-capped QDs yield emission above 1.3 µm at RT with a full width at half maximum (FWHM) of ∼44 meV [Fig.…”

“…ince the proposal of Arakawa and Sakaki more than three decades ago, 1) research on quantum dots (QDs) has been gaining increasing interest, owing to their unique physical properties arising from the three-dimensional quantum confinement of carriers and delta-like density of states. QDs find many applications, especially in photonic devices such as lasers, 2) photonics crystals, 3) solar cells, 4) and photodetectors. 5) Lasers using QDs as a gain medium exhibit improved device characteristics, such as ultralow threshold current density and high temperature stability, unattainable by their quantum well counterparts, 1) and have found widespread commercial applications.…”

MBE growth of P-doped 1.3 μm InAs quantum dot lasers on silicon

“…This has impeded the development of high quality long wavelength InAs quantum dot lasers in MOCVD due to the relatively hotter growth temperatures needed for efficient precursor pyrolysis. 15 Our improved growth conditions show no significant PL degradation under prolonged annealing at typical GaAs/AlGaAs growth temperatures of 600 C. On the other hand, quantum dots grown with the original conditions show a 20 nm peak wavelength blueshift and a 6 meV increase in linewidth after annealing. The improvement is hypothesized to arise from the colder growth temperatures and faster growth rates, which suppresses initial In-Ga intermixing during the quantum dot growth and the capping layer growth.…”

1.16 μm InAs/GaAs Quantum Dot Laser grown by Metal Organic Chemical Vapor Deposition

“…Generally speaking, there are two ways to grow semiconductor QD laser structures, i.e., molecular beam epitaxy (MBE) and metal organic chemical vapor deposition (MOCVD). Although many QD lasers grown by MBE or MOCVD have been demonstrated [6][7][8][9][10][11][12], it is still a challenge to grow QDs by MOCVD with a luminescence wavelength near or beyond 1.3 µm due to the formation of incoherent islands in the epitaxial process. However, as MOCVD growth is much more suitable for industrial application than MBE, researchers have been focusing on QDs with high optical quality grown by MOCVD and corresponding QD lasers which are operating under continuous wave (CW) mode at room temperature [12,13].…”