Molecular beam epitaxial growth of CdMnSe as a promising material for spin injection

Summary form only given, as follows. Heterostructures containing CdMnSe on InAs are promising candidates for the successful electrical injection of spin polarized electrons into a narrow band gap semiconductor. For a manganese concentration of about 12% the dilute magnetic semiconductor is lattice matched to InAs and therefore can be grown unstrained. Using InAs also provides the opportunity to grow transport structures containing a high mobility two dimensional electron gas, which allows us to measure spin related transport phenomena in the ballistic transport regime. The growth of CdMnSe layers on InAs depends strongly on the preparation of the interface between the materials. The introduction of a ZnTe buffer layer improves considerably the quality of the CdMnSe. This was checked by X-ray diffraction (XRD) and photoluminescence (PL) measurements. Samples for electron transport from the CdMnSe through the InAs substrate were grown with different interface configurations. Transport measurements at low temperatures (0.4 to 4K) and magnetic fields up to 8T of these samples show a strong positive magnetoresistance. In order to extract effects of the CdMnSe itself, CdMnSe layers were grown on undoped AlGaSb/GaAs structures and their electrical properties were measured. Details of the growth, data from the characterization, as well as results from the transport measurements will be presented.