What is it about?
Varying the properties of the waveform used to drive an electron ratchet, seeing how to optimize the current, and comparing the experimental results to an analytical model. We initially drove our ratchet (Kedem et al., PNAS 2017) using a simple sine wave; work in the literature used basic on/off drives. But, surely the temporal drive can be optimized? There has been very little work in the literature, so we set out to explore the topic. We replaced the sine wave with a square wave, and modified the duty ratio (the fraction of time spent in the positive state). We find a rather complicated relationship, but the behavior can be approximated very well with a previously published analytical model. With it, we explain the symmetry-breaking mechanism that enables the use of unbiased drives (sine, 0.5 duty ratio square), and explain how to optimize the current.
The following have contributed to this page: Dr Ofer Kedem