Continuously tunable distributed feedback laser diode

The fabrication and performance characteristics of a monolithically integrated thermoelectric controlled single frequency distributed feedback laser diode are reported. The emission frequency of the laser can be continuously tuned by ∼±5 Å using a 50-mA controller current. This fine tuning is useful for coherent system applications and for resonant optical amplifiers used as repeaters. We also report a multiwavelength laser array, each emission frequency of which can be independently tuned. Such sources are potentially useful for closely spaced wavelength multiplexed systems.