Optimization of Near and Far Field Patterns in de InxGa1-xN Lasers

Abstract

In this work, the influence of the thickness of the n and p-GaN layers over near and far field patterns is analyzed for In_xGa_1-xN multiquantum well (MQW) laser structures. Two different optical cavities were considered, the conventional step separate confinement heterostructure (SCH-recta) and a graded-index (GRIN-SCH) structure with a parabolic variation of the Al content in the Al_xGa_1-xN guide layers. We found that for specific combinations of the thicknesses of the GaN layers the undesired ripples in the near and far-field patterns due to the insufficient Al_xGa_1-xN cladding layer thickness can be eliminated, being this an alternative solution to the problem to growth thick Al_xGa_1-xN cladding layers with higher aluminium content (x > 0.13).