structures. Two different optical cavities are compared, the conventional step separate
confinement heterostructure (Step) and a graded-index (GRIN) structure with a parabolic
variation of the Al content in the AlxGa1− xN guide layers. A comparison is made regarding
the confinement factor, near-and far-field patterns. An anomalous behavior for the
confinement factor is observed in the structure, and it can be eliminated by choosing an …