Low threshold current dual wavelength planar buried heterostructure lasers with close spatial and large spectral separation

Abstract
A novel technique for achieving closely spaced laser devices with large, but well-controlled, wavelength separation is described. Preferential population of the lowest band-gap active region in a stacked active layer structure is used along with patterned etching of the long wavelength active regions and regrowth over all devices to achieve the desired wavelength. Dual-wavelength dual-stripe buried heterostructure lasers with 5 μm stripes on 20 μm centers formed by impurity-induced layer disordering in a stacked active layer structure have threshold currents of 9.1 and 10.9 mA for laser wavelengths of 846 and 760 nm, respectively.