Numerical studies of transport properties through artificial atoms under magnetic fields

The many-body states in an artificial atom and its transport properties have been examined by numerical studies. The magnetic field dependence of both the ground state and low-lying excited states, obtained by the exact diagonalisation method, is in good agreement with experimental results. We have proposed two possible mechanisms for the anomalous T dependence of conductance peak heights. With increasing magnetic field, the correlation effect becomes stronger, which suppresses the conductance considerably.