Title :
Electroabsorption waveguide modulators at 1.3 μm fabricated on GaAs substrates
Author :
Loi, K.K. ; Shen, L. ; Wieder, H.H. ; Chang, W.S.C.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., San Diego, La Jolla, CA, USA
Abstract :
An InGaAs-InAlAs multiple-quantum-well (MQW) electroabsorption (EA) waveguide modulator fabricated on a GaAs substrate has been designed and characterized at 1.3-μm wavelength for microwave signal transmission on an analog fibre-optic link. The modulator structure with a lattice constant 2.5% larger than that of GaAs is grown upon a 0.7-μm-thick three-stage compositionally step-graded In/sub z/Al/sub 1-z/As relaxed buffer. The waveguide modulator exhibits a high-electrooptic slope efficiency of 0.56 V/sup -1/, a 3-dB electrical bandwidth of 20 GHz, and a large optical saturation intensity in excess of 17 mW. These high-speed optoelectronic modulators could potentially be integrated with on-chip GaAs electronic driver circuits.
Keywords :
III-V semiconductors; aluminium compounds; electro-optical modulation; electroabsorption; gallium arsenide; indium compounds; infrared sources; integrated optics; optical communication equipment; optical fabrication; optical saturation; semiconductor quantum wells; /spl mu/m wavelength; 0.7 mum; 1.3 mum; 17 mW; 20 GHz; GaAs; GaAs substrate; GaAs substrates; InGaAs-InAlAs; InGaAs-InAlAs MQW electroabsorption waveguide modulator fabrication; analog fibre-optic link; electrical bandwidth; electroabsorption waveguide modulators; high-electrooptic slope efficiency; high-speed optoelectronic modulators; large optical saturation intensity; lattice constant; microwave signal transmission; modulator structure; on-chip GaAs electronic driver circuits; three-stage compositionally step-graded In/sub z/Al/sub 1-z/As relaxed buffer; Bandwidth; Driver circuits; Gallium arsenide; Intensity modulation; Lattices; Optical buffering; Optical saturation; Optical waveguides; Quantum well devices; Signal design;
Journal_Title :
Photonics Technology Letters, IEEE
