Abstract

A monolithically integrated multiple-wavelength laser array is an attractive alternative to a bank of laser sources, which must be individually packaged and carefully wavelength-selected for wavelength-division multiplexing (WDM) applications. A linear array of 20 DFB lasers with a wavelength spacing of 1 nm has been recently demonstrated.¹ However, the maximum number of lasers that can be integrated in a one-dimensional array is limited. In contrast, a two-dimensional array of surface-emitting lasers can provide hundreds of independent wavelengths through a very simple control during the wafer-growth step.² The wavelength spacing is uniform and can be as small as a fraction of an angstrom or as large as several nanometers. The wavelength variation can also be controlled so that, for example, an N×N surface-emitting laser (SEL) array can provide either as few as N or as many as N×N independent wavelengths, where N can be as large as 50. SEL arrays may, therefore, be very important for WDM-based optical interconnects, optical signal processing, and related optical-network applications, especially when used in conjunction with a two-dimensional optical filter array.

© 1991 Optical Society of America