InGaAs-GaAs Quantum-Dot Mode-Locked Laser Diodes: Optimization of the Laser Geometry for Subpicosecond Pulse Generation

• Published in: IEEE photonics technology letters Vol. 21; no. 5; pp. 307 - 309
• Main Authors: Rae, A.R., Thompson, M.G., Kovsh, A.R., Penty, R.V., White, I.H.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.03.2009; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Conferences; Diode lasers; Fiber optics; Gallium arsenide; Geometrical optics; Holes; Laser diodes; Laser mode locking; Lasers; Mode-locked lasers; Optical fibers; Optical materials; Optimization; Power generation; Pulse generation; Quantum dot lasers; Quantum dots; quantum dots (QDs); semiconductor lasers; Space vector pulse width modulation
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2008.2010778

The effect of cavity geometry on both pulsewidth and pulse output power is systematically investigated for a monolithic mode-locked quantum-dot laser diode. Subpicosecond pulse generation is demonstrated, and trends in pulsewidth and pulse output power are correlated to the ratio of the gain-to-absorber section lengths. A three-fold reduction in the pulsewidth, from 2.3 ps to 800 fs, is observed for a change in the gain-to-absorber section length ratio of 14 : 1 to 3 : 1. In addition, an associated five-fold increase in average power and 14-fold increase in peak power are also observed.