Biological motors, such as the myosin-actin system responsible for muscle contraction, rectify Brownian motion using asymmetry and chemical energy. This type of rectification mechanism is called a ratchet, and has been implemented in artificial systems. Ratchets are non-equilibrium devices producing directed transport without an overall applied bias. Ratchets operate by breaking spatial and time-reversal symmetries through the application of a time-dependent potential with locally asymmetric features. In this talk, I will highlight some of our recent explorations of electron ratchets, using both experiment and theory. We find complex, unintuitive behaviors, with high sensitivity to structural and operating parameters, leading to effects such as current reversals. I will detail some promising features of a new experimental ratchet design, as well as a proposed photovoltaic device based on the ratchet principle.
