In this work, the spin-valley dependent transmission properties in magnetic superlattices (MSLs) based on monolayer transition metal dichalcogenides, especially tungsten diselenide ${\mathrm{WSe}}_2$, are studied. Ferromagnetic strips and top electrostatic gates are periodically distributed to generate the superlattice profiles, where the former induce the magnetic proximity effect in the two-dimensional material. Using the transfer matrix method, the spin-valley transmission channels are numerically calculated for parallel (PM) and antiparallel magnetization (AM). We calculate the Bloch wave vector to corroborate the transmission minibands and minigaps of MSLs. We obtain perfect valley polarization states for both PM and AM; however, well-defined spin polarization states are absent. When structural asymmetry is induced in MSLs, two well-defined spin-valley polarization states for both magnetization configurations are established. More importantly, these states can be accessed by switching the magnetization direction. As the period number increases the regions of perfect spin-valley polarization enhance and become broader. A TMR with negative values is obtained. The so-called anomalous transport characterized by a negative TMR is the result of the particular spin-valley splitting of the valence band. In short, magnetic ${\mathrm{WSe}}_2$ superlattices could be the basis for versatile devices with spin-valley polarization and magnetoresistive capabilities.

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• Dirac fermions
• Magnetoresistance
• Spintronics
• Valleytronics
• Transition metal dichalcogenides
• Landauer formula