  Using the Keldysh nonequilibrium Green function technique, we study the
current and shot noise spectroscopy of a single interacting quantum dot coupled
to two ferromagnetic leads with different polarizations. The polarizations of
leads can be both parallel and antiparallel alignments. General formulas of
current and shot noise are obtained, which can be applied in both the parallel
and antiparallel alignment cases. We show that for large polarization value,
the differential conductance and shot noise are completely diferent for spin up
and spin down configurations in the parallel alignment case. However, the
differential conductance and shot noise have the similar properties for
parallel alignment case in the small polarization value and for antiparallel
alignment case in any polarization value.
