Rough versus dilute interfaces in semiconductor heterostructures: The role of growth conditions

CdTe‐CdMnTe interfaces grown by molecular beam epitaxy are studied using excitons confined in quantum wells. For increasing growth temperatures Zeeman splittings indicate an enhanced dilution of Mn ions at the interface while the optical linewidths evidence a decreasing roughness. These results directly illustrate the fact that the two methods are sensitive to different scales of interface broadening.