Graphene edge spins: spintronics and magnetism in graphene nanomeshes

We have fabricated low-defect graphene nanomeshes (GNMs) by using a non-lithographic method and observed large-amplitude ferromagnetism even at room temperature, only when pore edges of the GNMs were hydrogen-terminated. The observed correlation between the inter-pore spacing and magnetism and also magnetic force microscope observations suggest that it is attributed to polarzied electron spins localized at the zigzag-type atomic structured pore-edges. The magnetic moment per edge dangling bond ($\sim$0.3 $\mu$B) is also in quantitative agreement with two theories. Moreover, a spin pumping effect is found for fields applied in parallel with the GNM planes in few-layer ferromagnetic GNMs, while a magnetoresistance (MR) hysteresis loop is observed under perpendicular fields. The present ferromagnetic GNMs must also realize rare-element free, invisible, flexible, and ultra-light (wearable) magnets and spintronic devices, which can overcome environmental and material-resource problems.