Title :
Gain, index variation, and linewidth-enhancement factor in 980-nm quantum-well and quantum-dot lasers
Author :
Rodríguez, D. ; Esquivias, I. ; Deubert, S. ; Reithmaier, J.P. ; Forchel, A. ; Krakowski, M. ; Calligaro, M. ; Parillaud, O.
Author_Institution :
Dept. de Tecnologia Fotonica, Univ. Politecnica de Madrid, Spain
Abstract :
An experimental comparative study of the gain, index variation, and linewidth enhancement factor in 980-nm quantum-well (QW) and quantum-dot (QD) lasers structures, designed for high power applications, is presented. The gain spectra of the QW lasers at high injection level revealed three different transition energies, with a low linewidth enhancement factor (∼1.2) for E2HH2 transitions. Similar values for the linewidth enhancement factor, ranging between 2.5 and 4.5, were found for QW and QD devices, when comparing at similar values of the peak gain. This result is attributed to the contribution of excited state transitions in the measured QD lasers.
Keywords :
excited states; quantum dot lasers; quantum well lasers; refractive index; spectral line breadth; 980 nm; excited state transitions; gain spectra; high injection level; high-power applications; index variation; linewidth-enhancement factor; quantum well lasers; quantum-dot lasers; transition energies; Laser beams; Laser excitation; Laser transitions; Optical design; Power lasers; Quantum dot lasers; Quantum dots; Quantum well lasers; Semiconductor lasers; Waveguide lasers;
Journal_Title :
Quantum Electronics, IEEE Journal of
DOI :
10.1109/JQE.2004.840083
