Abstract

Distributed-feedback (DFB) laser arrays are compact and attractive light sources for wavelength-division multiplexed lightwave communication systems and multiwavelength optical networks. Previously. 20-DFB laser arrays (20-nm total wavelength span).¹ 4-distributed Bragg reflector laser arrays (10-20 nm total wavelength span),² and 4-DFB laser arrays (40-nm total wavelength span)³ have been reported in the 1.5 μm wavelength region. A quantum well active layer has a broad gain spectrum due to the steplike density of states. A compressive-strained quantum well active layer has an even broader gain spectrum. because the strong band-filling effect occurs not only in the conduction band but also in the valence band due to the light-holelike in plane hole effective mass resulting from the compressive strain.⁴ In this work, we report the fabrication and performance of 20-wavelength DFB laser arrays with compressive-strained MQW active layers to achieve a record (to our knowledge) wide wavelength span of 131 nm in the 1.5 μm wavelength region. Moreover, the intrinsic amplitude modulation response has been characterized as a function of wavelength detuning by a parasitic-free optical modulation technique.⁵

© 1992 Optical Society of America