Experimental and theoretical study of high temperature-stability and low-chirp 1.55 mu m semiconductor laser with an external fiber grating

摘要

An experimental and theoretical study of the effect of temperature on the static and dynamic characteristics of packaged external fiber grating semiconductor lasers (FGL) is reported on. Operating in single frequency mode, the laser exhibits high output power (>8 mW), high temperature stability of operating frequency (-3.4 GHz/K), and low static chirp (-60 MHz/mA). The observed hysteresis in wavelength versus temperature dependence is explained in the frame of a time-domain FGL model accounting for asymmetric nonlinear gain. The laser has low dynamic chirp (similar to 16 MHz/mA) under 2.5 GB/s direct modulation, which is the key factor determining low penalty transmission over 312 km of SSM fiber. Dense WDM transmission performed at 2.6 Gbit/s over 117 km of SSM fiber shows that an FGL-based transmitter is a factor of 7 more tolerant to temperature variations than externally modulated DFB lasers. [References: 32]