  We in this paper study theoretically the spin-polarized quantum transport
through a T-shape quantum dot-array by means of transfer-matrix method along
with the Green^{,}s function technique. Multi-magnetic fields are used to
produce the spin-polarized transmission probabilities and therefore the spin
currents, which are shown to be tunable in a wide range by adjusting the
energy, and the direction-angle of magnetic fields as well. Particularly the
opposite- spin- polarization currents separately flowing out to two electrodes
can be generated and thus the system acts as a spin splitter.
