Versatile device structures in MoS₂: magnetic switching of perfect spin and valley polarization states as well as tunneling magnetoresistance

Abstract We show for the first time versatile device structures in MoS 2 or ferromagnetic MoS 2 junctions with two well-defined spin and valley polarization states accessible by switching the magnetization direction as well as effective tunneling magnetoresistance (TMR). We study Ferromagnetic/Ferromagnetic Insulator/Normal Metal (FM/FI/NM) junctions, finding spin–valley polarization and negative TMR. However, two well-defined valley polarization states accessible by reversing the magnetization direction are not possible. As an alternative, we consider FM/NM/FI MoS 2 junctions, obtaining two well-defined polarization states for both the spin and valley degrees of freedom. The states are accessible by switching the magnetization direction in the FI region. Here, it is fundamental to apply electrostatic gating in the NM region to ensure the participation of holes in the electronic transport. FM/NM/FI MoS 2 junctions also show high positive TMR values at the edges of the valence and conduction band.