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Disputation Ismet Gelen

17.04.2023 | 16:15
Thema der Dissertation:
Magnetism and structure of MnxAu1-x on Cu(001) and Ag(001)
Abstract: Mn-Au alloy has several AFM phases. Mn2Au might be very significant for future spin-electronic applications due to its noncentrosymmetric spin structure that allows for electrical manipulation. The thin films were prepared with electron-beam evaporators in ultra-high vacuum. We studied MnxAu1-x films in detail to investigate their structure for a variety of thicknesses and concentrations on Cu(001) and Ag(001) single crystals by means of low energy electron diffraction (LEED), medium-energy electron diffraction (MEED), Auger electron spectroscopy (AES), and scanning tunneling microscopy (STM).
We observed a c(2x2) superstructure for coverages between 0.5 and 1 ML of MnxAu1-x on Cu(001). MnxAu1-x revealed MEED oscillations during growth on Cu(001), but no LEED patterns could be observed for thicker films (> 1 ML). For studying the magnetic properties of AFM MnxAu1-x on Cu(001), we grew Co on top; then, we employed MOKE after zero-field cooling as well as after field cooling. We observed coercivity changes with temperature but did not observe any exchange bias. The MnxAu1-x showed MEED oscillations during growth on Ag(001). Fe/ MnxAu1-x bilayers on Ag(001) were studied magnetically by MOKE. We did not observe any significant change in coercivity to confirm the antiferromagnetism of the MnxAu1-x films.

Zeit & Ort

17.04.2023 | 16:15

Hörsaal B (0.1.01)
(Fachbereich Physik, Arnimallee 14, 14195 Berlin)