The introduction of phosphorus and arsenic dopants into bulk Cd1−xMnx Te crystals grown by the Bridgman-Stockbarger technique has been studieA-with respect to the resulting optical properties. Samples with a Mn composition in the range 0.10 < x < 0.30, both as-grown and annealed, were investigated. A combination of room temperature transmittance and reflectance measurements over the spectral range from the ultraviolet to the far infrared has been used to gain information concerning the structural quality of the samples. Low temperature photoluminescence measurements (1.6−5 K) were used to determine optical quality and excitonic energies.

Double beam photoconductivity experiments are reported for the system Cd1−xMnxTe. The technique allows a separation of surface and bulk contributions, respectively. Bulk effects dominate for manganese rich material and reveal a sharp peak at the band gap energy while surface conductivity reveals a step function type spectral behavior. The growth of a native oxide on the surface causes an increase in the surface recombination velocity and a change from surface to bulk conduction. An oxide related trap state was discovered that is located at approximately 400 meV above the valence band edge.

Application of moderate external electric fields to ZnSe/(Zn,Mn)Se superlattices is shown to yield readily measurable spectral shifts of the exciton ground state resonance in the quantum well limit. This shows that confinement effects increase the classical field ionization threshold. At high applied fields and low temperatures, externally injected hot electron excited luminescence from internal excitations of the Mn-ion is observed.

Photoluminescence, transmission, and reflectance measurements have yielded information about the states defining an optical gap in thin films and superlattices based on the (Pb,Eu)Te system, including the limit of high Eu concentration. Magneto-optical measurements show the presence of finite spin exchange processes at low Eu-concentrations.

At the time being, there is evidently a sharp increase of interest in growth of low-dimensional thin-film structures of semiconducting compounds by the Atomic Layer Epitaxy (ALE) method. Many of the wide-gap II-VI compounds can be grown from elemental source materials by an ALE mode related to Molecular Beam Epitaxy (MBE). This paper concentrates on recent ALE work involving ZnSe- and CdTe- derived diluted magnetic semiconductors (DMS) where a fraction of Zn or Cd is substituted by Mn atoms. It shows that Zn1-xMnxSe/ZnSe and Cd1-xMnxTe/CdTe DMS structures with abrupt interfaces and high structural perfection can be produced at low growth temperatures by the ALE method.