LOW-THRESHOLD CURRENT DUAL-WAVELENGTH PLANAR BURIED HETEROSTRUCTURE LASERS WITH CLOSE SPATIAL AND LARGE SPECTRAL SEPARATION

A novel technique for achieving closely spaced laser devices with larg e, but well-controlled, wavelength separation is described. Preferenti al population of the lowest band-gap active region in a stacked active layer structure is used along with patterned etching of the long wave length active regions and regrowth over all devices to achieve the des ired wavelength. Dual-wavelength dual-stripe buried heterostructure la sers with 5 mum stripes on 20 mum centers formed by impurity-induced l ayer disordering in a stacked active layer structure have threshold cu rrents of 9.1 and 10.9 mA for laser wavelengths of 846 and 760 nm, res pectively.