Pumping in an interacting quantum wire

We study charge and spin pumping in an interacting one-dimensional wire. We show that a spatially periodic potential modulated in space and time acts as a quantum pump, inducing a dc-current component at zero bias. The current generated by the pump is strongly affected by the interactions. It has a power-law dependence on the frequency or temperature, with the exponent determined by the interaction in the wire, while the coupling to the pump affects the amplitudes only. We also show that pure spinpumping can be achieved without the presence of a magnetic field.