Distinctive Magnetotransport of Graphene p-n-p Junctions via Resist-Free Fabrication and Controlled Diffusion of Metallic Contact

Graphene junction devices have revealed unique electrical transport properties (Young and Kim in Ann Rev Conden Ma P 2:101 [1]), including quantum interference (Young and Kim in Nat Phys 5:222 [2]; Satoru et al. in Jpn J Appl Phys 52:110105 [3]), Klein tunneling (Katsnelson et al. in Nat Phys 2:620 [4]; Shytov et al. in Phys Rev Lett 101:156804 [5]), and the fractional-valued quantum Hall effect (Ozyilmaz et al. in Phys Rev Lett 99:166804 [6]), which are absent in homogeneous graphene.