Abstract
A technique for setting the absolute frequency of a 1.5- mu m two-section distributed Bragg reflector (DBR) laser using an Er:YAG optical filter as a frequency discriminator is described. The absolute frequency of the laser was controlled with an accuracy better than 300 MHz over a tuning range of several hundred gigahertz. The frequency drift with laser temperature was -130 MHz/ degrees C, and the tuning rate with current in the active region was 40 MHz/mA.