Memory effects in electrochemically gated metallic point contacts

Electrochemical gating permits the observation of few-atom processes in contact reconstruction. We monitor the junction conductance during the opening and closing of an atomic-scale metallic contact and use this as an instantaneous probe of the atomic-scale structural switching process. We observe clear correlations in the quantum conductance of a contact in subsequent switching events, demonstrating memory effects at the atomic scale. These experimental observations are supported by numerical simulations which show a conservation of the contact reconstruction process across several switching cycles. These results open a route to electrochemically control few-atom surface reconstruction events with present-day detection capabilities.