Monday, April 23, 2012

1204.4598 (S. M. Badalyan et al.)

Plasmon and dielectric background inhomogeneity enhancement of Coulomb
drag in graphene double-layer structures
   [PDF]

S. M. Badalyan, F. M. Peeters
The drag of massless fermions in graphene double-layer structures is investigated in a wide rage of temperatures and inter-layer separations. We show that the inhomogeneity of the dielectric background in such graphene structures for experimentally relevant parameters results in a significant enhancement of the drag resistivity. At intermediate temperatures the dynamical screening via plasmon-mediated drag enhances the drag resistivity and results in an upturn in its behavior at large inter-layer separations. In a range of inter-layer separations, corresponding to the strong-to-weak crossover coupling of graphene layers, we find that the drag resistivity decreases approximately quadratically with the inter-layer spacing. This dependence weakens with a decrease of the inter-layer spacing while for larger separations we recover the cubic (quartic) dependence at intermediate (low) temperatures.
View original: http://arxiv.org/abs/1204.4598

No comments:

Post a Comment