Investigation of Atomic Layer Futuristic Memory Devices of Binary Chalcogenides WX2 (X = S and Se): First-Principles Study

We have investigated the spin-dependent structural, electronic and localized-induced magnetic moment in an atomic layer of binary chalcogenide semiconductors, Tungsten sulphide/selenide (WX2, where X= S, Se) using first-principle calculations. It was observed that the addition of fluorine to the WX2 monolayer lattice reduces the bandgap of the material and induced a magnetic moment of ~1 Bohr magneton. Moreover, the reasons behind this magnetic transition from non-magnetic semiconductors to magnetic semiconductors were investigated and discussed. The calculated binding energy reveals that the pristine monolayer is more stable than the fluorine doped WX2 sheet. Also, intermittent energy levels were created due to the fluorine atoms and resulted in p-type acceptor semiconductor behaviour in spin up and n-type donor behaviour in spin-down of WX2 monolayer. It was observed that the unparalleled behaviour of spin can be tuned to suitable applications such as memory devices and spintronics.