Spin tunneling in two-dimensional transition-metal dichalcogenide layers

The spin tunneling effect are studied using magnetic tunneling junctions (MTJs) with two-dimensional (2D) transition-metal dichalcogenide MX$_{\mathrm{2}}$ (M$=$Mo, W; X$=$S, Se) monolayers as the tunnel layers. The single-crystalline 2D MX$_{\mathrm{2}}$ monolayers were grown using chemical vapor deposition. As-grown 2D MX$_{\mathrm{2}}$ were transferred and fabricated into MTJ devices using lithography process. Ferromagnetic metals Co and permalloy were employed as top and bottom layers in the MTJ devices. In this presentation, the spin valve effect at low- and room-temperatures is reported; the temperature dependence and bias dependence of spin tunneling effect are reported; the layer dependence of the spin tunneling effect is reported; the annealing effect on the MTJ device is reported; antiferromagnetic-layer (such as PtMn) coupling effect in the MTJ devices is reported. Finally, the performance of MTJ devices based on MoS$_{\mathrm{2}}$, WS$_{\mathrm{2}}$, MoSe$_{\mathrm{2}}$, and WSe$_{\mathrm{2}}$ are compared.