Plasmon and charge quantization effects in a double-barrier quantum wire

The nonlinear transport properties of a single-channel quantum wire in the presence of two impurities are investigated. Treating the electron interaction within the Luttinger model, Coulomb oscillations and Coulomb staircase phenomena are identified. Several limiting cases of transport are discussed. The regime of temperatures smaller than the discretization energy of the charge density mode in the dot is treated in detail. For weak to intermediate interaction strengths, the nonlinear current exhibits a peculiar: step-like behavior related to the activation of excited plasmonic states. The corresponding differential conductance shows sharp peaks with non-analytic power law line-shape typical of Luttinger liquids.