PGI-1 Seminar: Dr. Markus Meinert
A GW study of half-metallic Heusler compounds: on the influence of many-body corrections
- 27.Jun.2012 11:30
Department of Physics, Bielefeld University
Spin-based electronics (Spintronics) are routinely applied today in various fields. Among the most prominent are magnetic field sensors in hard disk drives. These are based on the giant magnetoresistance (GMR) or, more recently, the tunnel magnetoresistance (TMR). One key parameter of such devices is the effect amplitude, which is governed by the spin polarization of the electrodes at the Fermi energy. Half-metallic ferromagnets hold the promise of 100% polarization, and have been extensively studied in this context.
A range of ferromagnetic Heusler compounds has been predicted by Kohn-Sham density functional theory (DFT) to be half-metallic, and there are some experimental confirmations of these predictions. However, there are well-known conceptual problems with the physical interpretation of the Kohn-Sham eigenvalue spectra. In this talk, I will discuss the influence of many-body corrections within the GW approximation on the quasiparticle spectra of two prototypical, potentially half-metallic Heusler compounds.
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