We investigate spin transport in diffusive graphene nanoribbons with both clean and rough zigzag edges, and long-range potential fluctuations. The long-range fields along the ribbon edges cause the local doping to come close to the charge neutrality point forming p-n junctions with localized magnetic moments, similar to the predicted magnetic edge of clean zigzag graphene nanoribbons. The resulting random edge magnetization polarizes charge currents and causes sample-to-sample fluctuations of the spin currents obeying universal predictions. We show furthermore that, although the average spin conductance vanishes, an applied transverse in-plane electric field can generate a finite spin conductance. A similar effect can also be achieved by aligning the edge magnetic moments through an external magnetic field.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2013 Nov 12|
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics