Graphene-based spinmechatronic valve

Abstract

The interlayer twist between van der Waals graphene crystals led to the discovery of superconducting and insulating states near the magic angle. In this work, we exploit this mechanical degree of freedom by twisting the graphene middle layer in a trilayer graphene spacer between two metallic leads (magnetic and nonmagnetic). A large difference in conductance is found depending on the angle of twist between the middle layer graphene and the ones at the interface. This difference, called twisting resistance, reach more than 1000% in the non-magnetic Cu case. For the magnetic Ni case, the magneto-resistance decreases and the difference in conductance between twisted and not twisted depends strongly on the relative magnetization configuration. For the parallel configuration, the twisting resistance is about −40%, while for the anti-parallel configuration it can reach up to 130%. Furthermore, we show that the twisting resistance can be enhanced by inserting a thin Cu layer at the interface of Ni/graphene where it reaches a value of 200% and 1600% for parallel and antiparallel configurations, respectively. These findings could pave the way toward the integration of 2D materials on novel spinmechatronics based devices.