  We discuss the nonlinear Andreev current of an interacting quantum dot
coupled to spin-polarized and superconducting reservoirs when voltage and
temperature biases are applied across the nanostructure. Due to the
particle-hole symmetry introduced by the superconducting (S) lead, the subgap
spin current vanishes identically. Nevertheless, the Andreev charge current
depends on the degree of polarization in the ferromagnetic (F) contact since
the shift of electrostatic internal potential of the conductor depends on spin
orientation of the charge carrier. This spin-dependent potential shift
characterizes nonlinear responses in our device. We show how the subgap current
versus the bias voltage or temperature difference depends on the lead
polarization in two cases, namely (i) S-dominant case, when the
dot-superconductor tunneling rate ($\Gamma_R$) is much higher than the
ferromagnet-dot tunnel coupling ($\Gamma_L$), and (ii) F-dominant case, when
$\Gamma_L\gg \Gamma_R$. For the ferromagnetic dominant case the spin-dependent
potential shows a nonmonotonic behavior as the dot level is detuned. Thus the
subgap current can also exhibit interesting behaviors such as current
rectification and the maximization of thermocurrents with smaller thermal
biases when the lead polarization and the quantum dot level are adjusted.
