Superlattice heterostructures formed with single crystalline semiconductor nanomembranes and amorphous tunneling barrier layers

A quantum cascade laser comprising an active core embedded in an optical waveguide, the active core comprising a plurality of coupled laser stages, each stage comprising an electron injector, an active region coupled to the electron injector, and an electron extractor coupled to the active region, wherein the active regions comprises a semiconductor superlattice comprising alternating quantum barrier layers and quantum well layers, the quantum barrier layers comprising an amorphous inorganic material and the quantum well layers comprising a single-crystalline semiconductor.