[工程科技]Effect of gauge-field interaction on fermion transport in 2D Hartree conductivity correctio.pdfVIP

Effect of gauge-field interaction on fermion transport in 2D: Hartree conductivity correction and dephasing T. Ludwig,1 I. V. Gornyi,2, 3, ∗ A. D. Mirlin,2, 4, 3, † and P. W¨olfle4, 3, 2 1Instituut-Lorentz, Universiteit Leiden, P.O. Box 9506, 2300 RA Leiden, The Netherlands 2 Institut f¨ur Nanotechnologie, Forschungszentrum Karlsruhe, 76021 Karlsruhe, Germany 3 Center for Functional Nanostructures, Universit¨at Karlsruhe, 76128 Karlsruhe, Germany 4 Institut f¨ur Theorie der kondensierten Materie, Universit¨at Karlsruhe, 76128 Karlsruhe, Germany 8 (Dated: April 14, 2008) 0 0 We consider the quantum corrections to the conductivity of fermions interacting via a Chern- Simons gauge field, and concentrate on the Hartree-type contributions. The first-order Hartree 2 −1/2 approximation is only valid in the limit of weak coupling λ ≪ g to the gauge field r (g ≫ 1 is the dimensionless conductance), and results in an antilocalizing conductivity correc- p 2 2 tion ∼ λ g ln T . In the case of strong coupling, an infinite summation of higher-order terms A is necessary, including both the virtual (renormalization of the frequency) and real (dephasing)