Speaker
Description
For the spintronic applications like large data storages (high capacity HDD) the
industry search for ferromagnetic insulators and at the same time a very thin materials. Recently the discovery of Bi$_2$O$_2$Se/Te phases could exist as 2D material and still be semiconducting. Here we investigate these novel layer-structured materials with high electron mobility, while its efficiency could be greatly improved by doping different elements to introduce a magnetic spin order utilizing quite demanding quantum-mechanical calculations. We explore the electronic and magnetic properties of various ferromagnetic (e.g. Fe) or antiferromagnetic (e.g. Mn) transitional metals doped Bi$_2$O$_2$Se/Te phases within the framework of density functional theory based electronic structure calculations. We start with the magnetic order of the bulk phase in which the magnetic atoms form interlayer coupling that vary with the type and concentration of doped atoms and go towards the nanoscale dimension, i.e. 2D materials. As a result of the competitions of magnetic interactions the magnetic anisotropy energy is a crucial quantity leading to a potential spintronic material at the nano-scale dimensions. In combinations with Monte Carlo simulations we are able to solve the exchange interaction constants for the Heisenberg model and therefore evaluate another important quantity, the transition (Curie temperature) among the order and paramagnetic state of Bi$_{2-n}$X_n$O$_2$Se/Te to see if these types of materials are suitable to become novel dilute magnetic semiconductors for spintronic applications at room and above temperatures.
