Electroabsorption modulator performance predicted from band-edge absorption spectra of bulk, quantum-well, and quantum-well-intermixed InGaAsP structures

• Published in: Solid-state electronics Vol. 51; no. 1; pp. 38 - 47
• Main Authors: Morrison, Gordon B., Raring, James W., Wang, Chad S., Skogen, Erik J., Chang, Yu-Chia, Sysak, Matt, Coldren, L.A.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.2007; Elsevier Science
• Subjects: Applied sciences; Bandwidth; Bulk material; Chirp; Circuit properties; Compound structure devices; Electric, optical and optoelectronic circuits; Electroabsorption; Electronics; Exact sciences and technology; Exciton; Franz–Keldysh effect; Integrated optoelectronics. Optoelectronic circuits; Modulator; Optical and optoelectronic circuits; Photocurrent spectroscopy; Quantum confined Stark effect; Quantum well; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Tunable; Quantum well; Modulator; Exciton; Bulk material; Chirp; Bandwidth; Photocurrent spectroscopy; Tunable; Quantum confined Stark effect; Electroabsorption; Franz–Keldysh effect; Performance evaluation; Tunable circuit; Gallium arsenides; Indium phosphide; Absorption band; Electroabsorption modulator; Franz-Keldysh effect; Quantum effect; Gallium phosphide; Indium arsenides; Extinction index; Franz Keldysh effect; Quaternary compound; Insertion loss; Conduction band; Photoelectric current
• ISSN: 0038-1101; 1879-2405
• DOI: 10.1016/j.sse.2006.10.013

Band-edge absorption spectra from bulk, quantum-well, and quantum-well-intermixed InGaAsP material are collected and compared using photocurrent spectroscopy. The expected performances of ideal electroabsorption modulators fabricated from these materials are predicted and compared using the band-edge absorption data. A graphical method for simultaneously considering chirp, insertion-loss, extinction-ratio, and tuning range is presented, and is used to compare the suitability of the various materials for electroabsorption modulator applications. The quantum-well material is shown to be superior to bulk material for most EAM applications. Quantum wells with 85meV conduction band depth and 80Å width are shown to be superior to quantum wells with 120meV conduction band depth and 65Å width. Both well designs exhibit strong excitons. Finally, the effect of quantum-well intermixing is considered, and the expected performances of quantum-well-intermixed electroabsorption modulators are presented.