Regensburg 2019 – wissenschaftliches Programm
MA 36.2: Vortrag
Mittwoch, 3. April 2019, 15:15–15:30, H53
Tetragonal CuMnAs alloy: role of defects — •Frantisek Maca1, Josef Kudrnovsky1, Pavel Balaz2, Vaclav Drchal1, Karel Carva2, and Ilja Turek2 — 1Institute of Physics ASCR, Praha, Czech Republic — 2Charles University, Faculty of Mathematics and Physics, Praha, Czech Republic
The antiferromagnetic CuMnAs alloy with tetragonal structure is a promising material for the AFM spintronics. The resistivity measurements indicate the presence of defects about whose types and concentrations is more speculated as known. We confirmed vacancies on Mn or Cu sublattices and Mn on Cu and Cu on Mn antisites as most probable defects in CuMnAs by ab-initio total energy calculations.
We have estimated resistivities of possible defect types as well as resistivities of samples for which the X-ray structural analysis is available. In the latter case we have found that samples with Cu- and Mn-vacancies with low formation energies have also resistivities which agree well with the experiment.
Finally, we have also calculated exchange interactions and estimated the Neel temperatures by using the Monte Carlo approach. A good agreement with experiment was obtained.
 F. Maca, J. Kudrnovsky, V. Drchal, K. Carva, P. Balaz, and I. Turek, J. Magn. Magn. Mater. 474 (2019) 467.