Twisted bilayer graphene as a linear nanoactuator

We propose a linear actuation mechanism for twisted bilayer graphene. Using molecular dynamics simulations, we show that the translational motion of a layer can cause another layer to move in an orthogonal direction. Such an effect depends strongly on the crystallographic orientation of graphene with respect to the direction of displacement. For the cross junction between two graphene nanoribbons, we predict the existence of a linear and a nonlinear actuation regime separated by a critical bilayer twisting angle. This critical angle is determined by the overlap between the van der Waals interaction ranges of the moir\'e superlattice. Based on this mechanism, a linear nanoactuator with desired transmission efficiency can be designed by adjusting the interlayer twisting angle of bilayer graphene.