Microwave Energy Drives "On–Off–On" Spin-Switch Behavior in Nitrogen-Doped Graphene

The established application of graphene in organic/inorganic spin-valve
spintronic assemblies is as a spin-transport channel for spin-polarized
electrons injected from ferromagnetic substrates. To generate and control
spin injection without such substrates, the graphene backbone must be
imprinted with spin-polarized states and itinerant-like spins. Computations
suggest that such states should emerge in graphene derivatives
incorporating pyridinic nitrogen. The synthesis and electronic properties
of nitrogen-doped graphene (N content: 9.8%), featuring both localized
spin centers and spin-containing sites with itinerant electron properties,
are reported. This material exhibits spin-switch behavior (on–off–on)
controlled by microwave irradiation at X-band frequency. This phenomenon
may enable the creation of novel types of switches, filters, and spintronic
devices using sp2-only 2D systems.