Spectral analysis of InGaAs/GaAs quantum-dot lasers

Abstract

The cause of the unusual spectral distribution, often observed in InGaAs/GaAs quantum-dot lasers, is investigated by analyzing the spectra from devices fabricated with different substrate thickness (100-400 mu m). Using a Fourier transform analysis to determine the optical path length, it is found that the measured modulation period correlates with the device thickness. Such a result provides evidence for spectral modulation mediated by the device structure rather than the quantum-dot material itself and is consistent with the idea that the modulation is due to a mode propagating in the transparent substrate. (C) 1999 American Institute of Physics. [S0003-6951(99)02741-2]

Modelling the spectral emission of multi-section quantum dot superluminescent light-emitting diodes

“…We therefore associate the observed periodic spectral features, with period ∼2 nm and 20 nm with light leakage to transverse modes. The former is consistent with a single substrate mode [20,21], whereas the latter is likely to be a consequence of the beating between two substrate modes. The sectioning of the anode may also be a contributing factor.…”

Farfield characteristics of InGaAs/GaAs quantum dot laser

“…The optical mode that interacts with the gain producing region of the device was therefore a leaky mode 7 . It had been verified that such leaky modes could cause a modulation of the intensity of the emission spectra.…”

“…The spectra of InGaAs/GaAs quantum dots laser were consisted of groups of longitudinal modes or super-modes, which was presumably due to the feedback of the substrate [7][8][9] . The farfield characteristic of quantum dots laser was quite important for the utilization in communications, such as fiber coupling.…”

Long-Range Interface-Photon-Mediated Interactions between Self-Assembled Quantum Dots

“…A redistribution of the incoming energy, due to the optical or electrical pump, between the QDs is a key-process for QD lasing [4]. Usually, it is assumed that there are two main mechanisms of interaction between self-assembled QDs: tunneling and thermionic coupling.…”