Implication of Hydrogenation in Tuning the Magnetoresistance of Graphene-Based Magnetic Junction

Hydrogenation is suggested as a preferred method for opening bandgap (BG) in graphene for use in spintronic devices. Magnetoresistance (MR) in graphene is found to increase with hydrogenation, which is in contrast to MR obtained through other methods and in pristine graphene. Hydrogenation also results in higher spin filtration (SF) with increase in bandgap in comparison to their values obtained through other methods. Bandgap opening of around ~5.96 eV in graphene is obtained with hydrogenation. Results suggest that MR in hydrogenated structure is larger than the MR of pristine graphene. MR values of ~99% are observed with hydrogenation in comparison to ~90% MR in pristine structure (without hydrogenation). Spin-injection efficiency which is also a measure of spin-filtration is observed to be higher in hydrogenated graphene at around ~90%-100% in comparison to ~80%-90% in the pristine structure.