Proposal for Common Active 1.3- \mu m Quantum Dot Electroabsorption Modulated DFB Laser

• Published in: IEEE photonics technology letters Vol. 31; no. 6; pp. 419 - 422
• Main Authors: Sobhani, Soroush A., Stevens, Ben J., Babazadeh, Nasser, Takemasa, Keizo, Nishi, Kenichi, Sugawara, Mitsuru, Hogg, Richard A., Childs, David T. D.
• Format: Journal Article
• Language: English
• Published: IEEE 15-03-2019
• Subjects: Absorption; blue chirp; Chirp; Distributed feedback devices; distributed feedback laser; electroabsorption modulated laser; Erbium; Modulation; negative chirp; Quantum dot lasers; Quantum dots
• ISSN: 1041-1135; 1941-0174
• DOI: 10.1109/LPT.2018.2890641

Opportunities for the monolithic integration of a novel common quantum dot (QD)-active electroabsorption modulated laser are explored. An electric-field and temperature-dependent spectroscopic study of optical absorption and gain are presented in the state-of-the-art 1.3-μm In(Ga)As/GaAs QD active material. The unique gain/absorption spectral shape, attributed to the QD's density of states, allows for a number of possible modulation schemes dependent upon the selected laser wavelength detuning from the gain peak. Intensity modulation and change in absorption, leading to negative chirp operation, are demonstrated via absorption spectroscopy and gain measurement of eight-layer-stack QD-active material. Such a device would be able to provide positive or negative chirp dependent upon modulation scheme and gain/Bragg wavelength detuning.