  Brownian motors, i.e. devices able to produce useful work out of thermal
forces with the help of other unbiased forces, provide an ideal benchmark for
the investigation of quantum dissipative systems, for two reasons. First, the
interaction with a dissipative environment plays an essential role in the
performance of Brownian motors. Second, dissipative tunneling enriches the
dynamics of quantum Brownian motors with respect to their classical
counterpart, inducing features such as current reversals as a function of
temperature. Here we report on our work on quantum Brownian motors and discuss
the load characteristic of such a system.
