Speaker
Description
In recent years, the realization of magnetic long-range order in atomically thin 2D materials has shown a big potential in spintronic applications in ultrathin magnets due to the possibility of manipulation of magnetism by external fields, strain or proximity effects in van der Waals (vdW) heterostructures. Specifically, the family of 2D metallic magnets Fe$_n$GeTe$_2$ ($n=3, 4, 5$) has attracted a huge attention due to their high Curie temperatures and intriguing properties. A systematic study of the electronic structure and magnetism of Fe$_n$GeTe$_2$ magnets by ab initio density functional theory, calculations of interatomic exchange interaction parameters and Monte Carlo simulations will be shown highlighting the importance of electron correlation with the aid of dynamical mean field theory, spin-orbit coupling and effects of transition metal doping. Also, results on spin-polarized quantum transport calculations will be presented for PtTe$_2$/Fe$_4$GeTe$_2$/PtTe$_2$ van der Waals heterostructures. Finally, the effects of electrode polytypes on spin transport properties will be shown for a vdW heterostructure comprising of a ferromagnetic monolayer of 1T-VSe$_2$ with two structural polytypes (1T and 2H) of TaS$_2$ electrodes. It will be shown that the 1T-device shows superior performance with lower Gilbert damping, reduced critical current density and voltage for magnetization switching, compared to the 2H-device, which requires significantly higher current and voltage.
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[6] M. Davoudiniya, B. Sanyal, npj 2D Mater. Appl. (in press)
