High-speed intensity modulation of 1.5 mu m DBR lasers with wavelength tuning

Intensity modulation characteristics of a 1.5- mu m butt-jointed DBR (distributed-Bragg-reflector) laser with wavelength tuning were studied. A 3-dB modulation bandwidth of 9 GHz and a high relaxation oscillation frequency of more than 10 GHz were obtained for the DBR laser. These characteristics were not affected by changing the lasing wavelength. The chirping width of the DBR laser is lower than that of the distributed feedback (DFB) laser. A clear eye opening and low chirping characteristics were obtained under 5-Gb/s nonreturn to zero (NRZ) pseudorandom modulation with a sufficient extinction ratio.<
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