z/-z Symmetry of spin-orbit coupling and weak localization in graphene
  We show that the influence of spin-orbit (SO) coupling on the weak localization effect for electrons in graphene depends on the lack or presence of z/-z symmetry in the system. While for z/-z asymmetric SO coupling, disordered graphene should display a weak anti-localization behavior at lowest temperature, z/-z symmetric coupling leads to an effective saturation of decoherence time which can be partially lifted by an in-plane magnetic field, thus, tending to restore the weak localization effect. 
Edward McCann and Vladimir I. Fal'ko
cond-mat.mes-hall