Title :
Design and Fabrication of Low-Driving-Voltage Electroabsorption Modulators Operating at 40 Gb/s
Author :
Fukano, Hideki ; Yamanaka, Takayuki ; Tamura, Munehisa
Author_Institution :
NTT Photonics Lab., Atsugi
Abstract :
In this paper, a design for low-driving-voltage InGaAlAs/InAlAs electroabsorption modulators (EAMs) operating at 40 Gb/s is described. The theoretical calculation clarified that the tensile-strained InGaAlAs/InAlAs multiquantum-well layers with thin wells provide large and steep extinction characteristics. This was experimentally confirmed. We modeled an EAM with a low-loss coplanar waveguide for both the input and output ports and designed an optimized core structure that assures a sufficient extinction ratio and electrical-to-optical bandwidth for 40-Gb/s operation, in terms of well number and core length. A fabricated device driven by a peak-to-peak voltage as low as 1.1 V shows a 3-dB bandwidth of over 50 GHz and an RF extinction ratio of 10 dB. Error-free operation at 40 Gb/s is confirmed.
Keywords :
III-V semiconductors; aluminium compounds; coplanar waveguides; electro-optical modulation; gallium compounds; indium compounds; optical design techniques; optical fabrication; optical waveguides; semiconductor quantum wells; bit rate 40 Gbit/s; coplanar waveguide; electrical-to-optical bandwidth; electroabsorption modulators; tensile-strained multiquantum-well layers; thin wells; Bandwidth; Energy consumption; Extinction ratio; Fabrication; Indium compounds; Low voltage; Optical transmitters; Quantum well devices; Radio frequency; Time division multiplexing; EA modulator (EAM); InGaAlAs/InAlAs; electroabsorption (EA); low driving voltage;
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2007.901328
