Strain-Controllable Magnetism in Co Decorated Pyridinic N-Doped Graphene

An external strain is suggested as an effective means to finely control the magnetic properties of a candidate medium for future spintronics devices. To demonstrate the potential of this concept, the biaxial strain effects on the magnetic moment of Co adatom on pyridinic N-doped graphene (PNG) sheet were investigated using density functional theory calculations. Under the strain from -5% to 5%, the magnetic moment of the Co adatom on PNG was increased continuously from 1.72 to 1.95 μ_B. Also, Co adatoms are expected to be dispersed on the PNG surface without metal clustering in this range of applied strain due to its strong binding with the pyridinic nitrogen defects. From these results, it is anticipated that reliable control of magnetism in Co decorated PNG system is available by use of an external strain.