  We consider a single-electron transistor in the form of a ferromagnetic dot
in contact with normal-metal and pinned ferromagnetic leads. Microwave-driven
precession by the dot induces a pumped electric current. In open circuits, this
pumping produces a measurable reverse bias voltage, which can be enhanced and
made highly nonlinear by Coulomb blockade in the dot. The dependence of this
bias on the power and spectrum of microwave irradiation may be utilized to
develop nanoscale microwave detectors analogous to single-electron
transistor-based electrostatic sensors and nanoelectromechanical devices.
