Field effect in stacked van der Waals heterostructures: Stacking   sequence matters
  Stacked van der Waals (vdW) heterostructures where semi-conducting two-dimensional (2D) materials are contacted by overlayed graphene electrodes enable atomically-thin, flexible electronics. We use first-principles quantum transport simulations of graphene-contacted MoS2 devices to show how the transistor effect critically depends on the stacking configuration relative to the gate electrode. We can trace this behavior to the stacking-dependent response of the contact region to the capacitive electric field induced by the gate. The contact resistance is a central parameter and our observation establish an important design rule for devices based on 2D atomic crystals. 
Daniele Stradi, Nick R. Papior, Mads Brandbyge
cond-mat.mtrl-sci cond-mat.mes-hall