Low‐threshold (∼600 A/cm2 at room temperature) GaAs/AlGaAs lasers on Si (100)

Low‐threshold graded‐refractive‐index GaAs/AlGaAs laser structures were grown on Si (100) by molecular beam epitaxy and tested at room temperature under a probe station. Broad area devices having widths of 110–120 μm and cavity lengths of ∼500–1210 μm exhibited threshold current densities as low as 600 A/cm2 and total slope efficiencies of as high as 0.75 W/A. The thresholds fell in the range of 600–1000 A/cm2 in three different wafers, and it is assumed that the quality of the facets accounts for most of the spread in results.