Mechanical spin splitting in zigzag graphene nanoribbons

Graphene nanostructures, renowned for their exceptional electronic and transport properties, hold great promise for stretchable electronics. Zigzag graphene nanoribbons (ZGNRs) further intrigue with their intrinsic edge magnetism, unlocking new potentials in spintronic devices. In this paper, we integrate mechanical behavior with pi magnetism to establish a robust platform for mechanical spin splitting in ZGNRs. Our findings reveal fully spin-polarized states in a large energy window, exhibiting significant magnetic moments and tunable spin gaps in helicoidal ZGNRs. Substantial spin splitting occurs when helical morphologies lead to different bond lengths at one zigzag edge relative to the other. The spin-splitting and spin-gap characteristics within the bipolar spin-semiconducting phase can be precisely controlled by varying helical configurations and the magnitude of strain induced by deformation. This mechanical control over electronic and magnetic properties positions ZGNRs as a promising candidate for stretchable spintronic devices.