Current-confined multi-junction diode-laser bar

An edge-emitting diode-laser bar, comprising:

• a plurality of n-type layers;
• a plurality of p-type layers;
• a plurality of active regions, each of the plurality of active regions sandwiched between an adjacent n-type layer of the plurality of n-type layers and an adjacent p-type layer of the plurality of p-type layers to form one of a plurality of diode-laser junctions, the plurality of diode-laser junctions vertically arranged on a substrate to form a semiconductor structure;
• and
• at least one tunneling junction, adjacent diode-laser junctions having a tunneling junction located therebetween;
• wherein the p-type layer of each of the plurality of diode-laser junctions is overlaid by a current confinement layer, the current confinement layers laterally constraining current flow through the semiconductor structure.