An Eight-Wavelength BH DFB Laser Array With Equivalent Phase Shifts for WDM Systems

In this letter, we report an eight-wavelength monolithically integrated buried heterostructure distributed feedback laser array with quarter-wave equivalent phase shifts. The laser array operating at 1.3 mu m has a chip size of 2 mm x 250 mu m. Lasing channel spacing is designed to be 800 GHz (similar to 4.6 nm at 1.3 mu m). The laser array exhibits accurate wavelength control and stable single mode lasing operation over a wide range of injection currents and different ambient temperatures. The measured linewidth of these lasers is 278 kHz at 65-mA bias current. In addition, the lasing wavelength of the whole laser array can be tuned continuously over 38.3 nm without mode hopping. The proposed method offers a practical approach of integrated laser array fabrication for wavelength-division multiplexing systems.