Abstract:
We study tunneling of weakly-interacting electrons through a single delta-shaped potential barrier in one-dimensional mesoscopic wires and rings. Using the Hartree-Fock model we find results which reasonably reproduce the results known from Luttinger liquid models. In particular, the conductance of a wire of length L decays for large L as L^-2α, with the power α depending only on the electron-electron interaction. Similarly, we find that the persistent current in a mesoscopic ring of length L decays with the system length L as L^-1-α. We show that these power laws persist also in correlated many-body models: We include correlations by the quantum Monte Carlo method as well as by exact diagonalization. Both approaches give very close results.