Charge and spin addition energies of a one-dimensional quantum dot

We derive the effective action for a one-dimensional electron island formed between a double barrier in a single-channel quantum wire including the el ectron spin. Current and energy addition terms corresponding to charge and spin are identified. The influence of the range and the strength of the ele ctron interaction and other system parameters on the charge and spin additi on energies and on the excitation spectra of the modes confined within the island is studied. We find by comparison with experiment that spin excitati ons in addition to nonzero range of the interaction and inhomogeneity effec ts are important for understanding the electron transport through one-dimen sional quantum islands in cleaved-edge-overgrowth systems.