Spectral Analysis of 1.55-$\mu$m InAs–InP(113)B Quantum-Dot Lasers Based on a Multipopulation Rate Equations Model

Abstract

In this paper, a theoretical model is used to investigate the lasing spectrum properties of InAs-InP(113)B quantum dot (QD) lasers emitting at 1.55 m. The numerical model is based on a multipopulation rate equations analysis. Calculations take into account the QD size dispersion as well as the temperature dependence through both the inhomogeneous and the homogeneous broadenings. This paper demonstrates that the model is capable of reproducing the spectral behavior of InAs-InP QD lasers. Especially, this study aims to highlight the transition of the lasing wavelength from the ground state (GS) to the excited state (ES). In order to understand how the QD laser turns on, calculated optical spectra are determined for different cavity lengths and compared to experimental ones. Unlike InAs-GaAs QD lasers emitting at 1.3 m, it is shown that a continuous transition from the GS to the ES is exhibited because of the large inhomogeneous broadening comparable to the GS and ES lasing energy difference. Index Terms-Quantum dot (QD), rate equation, semiconductor laser. I. INTRODUCTION L OW-COST, directly modulated lasers will play a major role in the next generation telecommunication links (local and metropolitan area network) for uncooled and isolator-free applications. As a consequence, semiconductor lasers based on low-dimensional heterostructures such as quantum dot (QD) laser are very promising. Indeed, QD structures have attracted a lot of attention in the last decade since they exhibit many interesting and useful properties such as low threshold current [1],

Impact of gain compression factor on modulation characteristics of InGaAs/GaAs self-assembled quantum dot lasers

“…Simulation of quantum dot lasers with two lasing states for InGaAs/GaAs quantum dot lasers emitting in 1.3 lm wavelength is also presented in [12][13][14]. Similar studies for (113)B InAs/InP quantum dot lasers are considered in [15,16] Note that at high bias condition, it has been shown in the aforementioned studies that the transition of lasing state occurs from the ground state to the excited state. Differential gain and linewidth enhancement factor are studied in [17,18].…”

Enhanced Modulation and Noise Characteristics in 1.55 µm QD Lasers using Additional Optical Pumping

“…On the other hand, in addition to the cascade relaxations, a direct channel for relaxation of carriers from the WL to the GS is considered for 1.55µm InAs/InP QD lasers. This assumption is based on previous experimental reports on kinetics of these kinds of QD lasers [20]. Fig.…”

“…1 (a) The schematic of 1.55µm QD laser structure (b) Carrier transition times. An excess number of carriers are provided to the ES through absorption of the external optical pump [20].…”

Measurement and analysis of optical gain spectra in 1.6 to 1.8 μm InAs/InP (100) quantum-dot amplifiers

“…In the model the homogeneous and inhomogeneous broadening are taken into account as well as the occupation dependent capture times and temperature and energy level dependent escape times. Also we did not include the Auger effect (Grillot et al 2009) or any other many body effects, and no direct relaxation from WL to GS (Grillot et al 2009) or any other higher energy states in the dots (Rossetti et al 2008). Inclusion of these aspects would significantly increase the number and complexity of the equations and increase calculation times too much.…”

“…The modeling of QD materials is more involved than the modeling of bulk or quantum well gain material due to the inhomogeneous character of the QD gain material. Extensive QD models have been presented especially for In x Ga 1−x As/GaAs QD materials (Sugawara et al 2000;Gioannini and Montrosset 2007) but also for InAs/InP QD materials (Grillot et al 2009) Here we have simplified a commonly used QD amplifier model to calculate the small signal gain spectrum of the amplifiers and to fit a number of the model parameters to the experimental data. Three important parameters are the electron-hole transition energies of the wetting layer (WL), the excited state (ES) and the ground state (GS).…”