Title :
High-Speed, Low-Current-Density 850 nm VCSELs
Author :
Westbergh, Petter ; Gustavsson, Johan S. ; Haglund, Åsa ; Sköld, Mats ; Joel, Andrew ; Larsson, Anders
Author_Institution :
Dept. of Microtechnol. & Nanosci., Chalmers Univ. of Technol., Gothenburg
Abstract :
We report on the design, fabrication, and evaluation of large-aperture, oxide-confined 850 nm vertical cavity surface emitting lasers (VCSELs) with high modulation bandwidth at low current densities. We also compare the use of InGaAs and GaAs quantum wells (QWs) in the active region. Both VCSELs reach an output power of 9 mW at room temperature, with a thermal resistance of 1.9deg C/mW. The use of InGaAs QWs improves the high-speed performance and enables a small-signal modulation bandwidth of 20 GHz at 25degC and 15 GHz at 85degC. At a constant bias current density of only 11 kA/cm2, we generate open eyes under large-signal modulation at bit rates up to 25 Gbit/s at 85degC and 30 Gbit/s at 55degC.
Keywords :
III-V semiconductors; current density; gallium arsenide; high-speed optical techniques; indium compounds; laser beams; optical design techniques; optical fabrication; optical modulation; semiconductor lasers; semiconductor quantum wells; surface emitting lasers; thermo-optical effects; GaAs; InGaAs; VCSEL fabrication; bandwidth 15 GHz; bandwidth 20 GHz; current-density; high-modulation bandwidth; high-speed VCSEL design; oxide-confined vertical cavity surface emitting laser; power 9 mW; quantum well; small-signal modulation bandwidth; temperature 25 degC; temperature 293 K to 298 K; temperature 55 degC; temperature 85 degC; thermal resistance; wavelength 850 nm; High-speed modulation; optical interconnects; semiconductor lasers; surface-emitting lasers;
Journal_Title :
Selected Topics in Quantum Electronics, IEEE Journal of
DOI :
10.1109/JSTQE.2009.2015465
