  We investigate two schemes for pumping spin adiabatically from a ferromagnet
through an interacting quantum dot into a normal lead, which exploit the
possibility to vary in time the ferromagnet's magnetization, either its
amplitude or its direction. For this purpose, we extend a diagrammatic
real-time technique for pumping to situations in which the leads' properties
are time dependent. In the first scheme, the time-dependent magnetization
amplitude is combined with a time-dependent level position of the quantum dot
to establish both a charge and a spin current. The second scheme uses a uniform
rotation of the ferromagnet's magnetization direction to generate a pure spin
current without a charge current. We discuss the influence of an
interaction-induced exchange field on the pumping characteristics.
