Significantly enhanced magnetoresistance in monolayer WTe₂via heterojunction engineering: a first-principles study

The large non-saturating magnetoresistance (MR) of bulk WTe₂ is known to be greatly reduced in thin films with decreasing thickness. In this study, based on first-principles calculations, we demonstrate that 2D WTe₂ bonded to graphene, through a WTe₂/graphene van der Waals (vdW) heterojunction, can exhibit a significantly enhanced MR, which can be even larger than that of bulk WTe₂. Moreover, the MR shows a strong stacking-orientation-dependent behavior, which facilitates a tunable MR effect. Our findings illustrate a new route to enhancing the MR of WTe₂ and other 2D semimetals via heterojunction engineering, which is useful for a range of applications in information technology.