A heterostructure includes a substrate and a layer stack of layer pairs on the substrate. The heterostructure may be part of a field-effect transistor or light emitting device, such as a laser, an LED, or a quantum cascade emitter. Each of the layer pairs includes (i) a first nitride layer that includes a metal and (ii) a second nitride layer that includes aluminum and gallium. A material composition of the first nitride layer may be Al.sub.1-xM.sub.xN, where x is between 0.01 and 0.18, inclusive, and M includes one or more of a group-III element, a rare earth element, boron, and gallium. A material composition of the second nitride layer may be Al.sub.1-yGa.sub.yN, where y is between 0.85 and 1.0, inclusive.