Title :
Linewidth study of InAs-InGaAs quantum dot distributed feedback lasers
Author :
Su, H. ; Zhang, Leiqi ; Wang, R. ; Newell, T.C. ; Gray, A.L. ; Lester, L.F.
Author_Institution :
Center for High Technol. Mater., Univ. of New Mexico, Albuquerque, NM, USA
Abstract :
The linewidth of laterally loss-coupled distributed feedback (DFB) lasers based on InAs quantum dots (QDs) embedded in an InGaAs quantum well (QW) is investigated. Narrow linewidth operation of QD devices is demonstrated. A linewidth-power product less than 1.2 MHz /spl middot/ mW is achieved in a device of 300-μm cavity length for an output power up to 2 mW. Depending on the gain offset of the DFB modes from the QD ground state gain peak, linewidth rebroadening or a floor is observed at a cavity photon density of about 1.2-2.4×10/sup 15/ cm/sup -3/, which is much lower than in QW lasers. This phenomenon is attributed to the enhanced gain compression observed in QDs.
Keywords :
III-V semiconductors; distributed feedback lasers; gallium arsenide; indium compounds; laser cavity resonators; laser modes; quantum dot lasers; semiconductor quantum wells; spectral line broadening; DFB modes; InAs-InGaAs; InAs-InGaAs quantum dot lasers; InGaAs quantum well; cavity photon density; distributed feedback lasers; gain compression; ground state; linewidth rebroadening; narrow linewidth operation; quantum dot devices; quantum well lasers; Distributed feedback devices; Laser feedback; Laser theory; Optical materials; Power generation; Quantum dot lasers; Quantum well lasers; Temperature; Threshold current; US Department of Transportation;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2004.834547
