Spin filters based on two-dimensional materials Co 2 Si and Cu 2 Si

Spintronic devices have several advantages compared with conventional electronic devices, including non-volatility, faster data processing speed, higher integration densities, less electric power consumption and so on. However, we still face challenges for efficiently generating and injecting pure spin polarized current. In this work, we utilize two kinds of two-dimensional materials Co Si and Cu Si with both lattice match and band match to construct devices and then research their spin filter efficiency. The spin filter efficiency can be improved effectively either by an appropriate gate voltage at Co Si region, or by series connection. In both cases the filter efficiencies are much larger than two-dimensional prepared Fe GeTe spin valve and ferromagnetic metallic chairlike O-graphene-H. Also at a quite small bias, we obtain a comparable spin polarized current as those obtained in Fe GeTe spin valve and O-graphene-H obtained at a much larger bias.&#xD.