|CHEN Dong-Hai,YANG Mou,DUAN Hou-Jian et al. Electronic transport properties of graphene PN junctions with spin-orbit coupling. Acta Phys. Sin., , (): 00.|
Abstract We investigate the electronic transport properties of graphene pn junction with spin-orbit coupling. If the incident energy lies between the potentials of the two ends of the pn junction, the particle can penetrate the graphene pn junction by tunneling accompanied with electron-hole transition. The curve of conductance versus the Fermi energy shows steps and reaches its maximum when the Fermi energy aligns at the middle of the potentials of the p and n areas. As the length of graphene pn junction increases, the conductance decays exponentially. The spin-orbit coupling leads to a bulk energy gap and edge states. The gap dramatically reduces the conductance and the edge states result in an almost perfect conductance plateau. When the pn region is subjected by random doping impurities, conductance curves are no longer symmetrical in the case of weak doping, while in the strong doping case, the step structures are destroyed but the conductance plateau contributed by the edge states survives well.