Conductance and Fano factor in normal/ferromagnetic/normal bilayer graphene junction.

We theoretically investigate the transport properties of bilayer graphene junctions, where the ferromagnetic strips are attached to the middle region of the graphene sheet. In these junctions, we can control the band gap and the band structure of the bilayer graphene by using the bias voltage between the layers and the exchange field induced on the layers. The conductance and Fano factor (F ) are calculated by the Landauer–Büttiker formula. It is found that when the voltage between the layers or the exchange field are tuned, the pseudodiffusive (F = 1/3) transport turns into tunneling (F = 1) or ballistic transport (F = 0). By tuning the potential difference between the layers, one can control the spin polarization of the current.