Extremely small-chirp electroabsorption-modulator integrated distributed feedback laser diode with a shallow quantum-well absorption layer

• Published in: IEEE journal of quantum electronics 2002-08, Vol.38 (8), p.1075-1080
• Main Authors: Miyazaki, Y., Tada, H., Aoyagi, T., Nishimura, T., Mitsui, Y.
• Format: Article
• Language: English
• Subjects: Absorption; Applied sciences; Carriers; Chirp; Circuit properties; Diode lasers; Diodes; Distributed feedback devices; Distributed feedback lasers; Electric, optical and optoelectronic circuits; Electroabsorption modulators; Electronics; Estimates; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Integrated optics. Optical fibers and wave guides; Lasers; Life estimation; Lifetime estimation; Optical and optoelectronic circuits; Optical elements, devices, and systems; Optical feedback; Optical modulation; Optical processors, correlators, and modulators; Optics; Other integrated-optical elements and systems; Physics; Quantum electronics; Quantum well lasers; Quantum wells; Semiconductor lasers; laser diodes; Ultraviolet sources
• ISSN: 0018-9197; 1558-1713
• DOI: 10.1109/JQE.2002.801030

We have developed an extremely small-chirp electroabsorption modulator integrated with a distributed feedback laser diode (EAM-DFB-LD) with a novel shallow quantum-well (QW) absorption layer. By using a shallow QW absorption layer, the estimated lifetime of the photogenerated holes and thus the estimated concentration of the holes generated by optical absorption has been reduced to 9% of that for a conventional QW. It was experimentally confirmed that the excess chirp due to the pileup of carriers has been reduced to 10% of that for a conventional QW, and this result is consistent with the estimates. The shallow QW EAM-DFB-LD has shown a chirp parameter |/spl alpha/| less than 0.7 over the entire range of the EAM reverse bias voltage of 0-3 V. Finally, successful 10-Gb/s return to zero transmission has been confirmed through both positive dispersion (+425 ps/nm) and negative dispersion (-425 ps/nm).