One- and Two-Dimensional Coherently Coupled Implant-Defined Vertical-Cavity Laser Arrays

Loss between elements of coherently coupled vertical-cavity surface-emitting laser (VCSEL) arrays typically causes out-of-phase operation with on-axis intensity nulls in the far-field. We show that in-phase evanescently coupled VCSEL arrays may be defined by proton implantation. An advantage for implanted in-phase coherently coupled VCSEL arrays is that this approach employs a simple and reliable fabrication process where the absence of loss between elements leads to in-phase coupling. We present data for 2, 3, and 4 element in-phase implant-defined coherently coupled VCSEL arrays.