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 (WX
2
, where X= S, Se) using first-principle calculations. It was observed that the addition of fluorine to the WX
2
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 WX
2
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 WX
2
monolayer. It was observed that the unparalleled behaviour of spin can be tuned to suitable applications such as memory devices and spintronics.