CdZnMgTe/CdZnTe superlattices were doped with nitrogen from a dc plasma source during their growth by molecular beam epitaxy. The samples were investigated by photoluminescence, double crystal x-ray diffraction, and secondary ion mass spectroscopy. A very strong intermixing across the quantum well interfaces was observed, producing a homogeneous alloy. The mixing is attributed to cation diffusion assisted by lattice defects generated by the simultaneous presence of Mg and N atoms. ©1997 American Institute of Physics.