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P. Mohn:
"p-Electron Magnetism in anion doped BaTiO_3-xX_x (X=C,N,B) and CdS";
Vortrag: Seminar Institut für Allgemeine Physik (IAP), TU Wien, Institut für Angewandte Physik; 29.11.2011.

We present VASP calculations using the HSE functional for carbon, nitrogen, and boron doped BaTiO3-xXx (X=C,N,B) and CdS1-xYx (Y= main group element). We calculate supercells and replace one oxygen atom by C,N, or B or a main group element for S in CdS. In the perovskite for all three substituents we find a magnetically ordered groundstate which is insulating for C and N and halfmetallic for B. The changes in the electronic structure between the undoped and the doped case are dominated by the strong crystal field effects together with the large band splitting for the impurity p-bands. Using an MO picture we give an explanation for the pronounced changes in the electronic structure between the insulating non-magnetic state and the as well insulating magnetic state for doped BaTiO3. For CdS we also find in most cases magnetic order, either halfmetallic or indulating. p-element doped perovskites and CdS could provide a new class of materials for various applications ranging from spin-electronics to magneto-optics.