  Electron spin filter induced by Zeeman splitting in a few-electron quantum
dot coupled to two normal electrodes is studied considering Coulomb blockade
effect. Based on the Anderson model and Liouville-von Neumann equation,
equation of motion of the system is derived and analytical solutions are
achieved. Transport windows for perfectly polarized current, partially
polarized current and non-polarized current induced by the Zeeman splitting
energy and Coulomb blockade potential are exploited. We will give the relations
of voltage, magnetic field and temperature for high quality spin filtering.
