Biased self-diffusion on Cu surface due to electric field gradients

Under strong electric fields, an arc of current flowing through plasma can link two metal surfaces even in ultra high vacuum. Despite decades research, the chain events leading to vacuum breakdowns is hitherto unknown. Previously we showed that a tall and sharp Cu nanotip exposed fields heats up by field emission currents eventually melts, evaporating neutral atoms contribute buildup. In this work, investigate means molecular dynamics simulations whether surface diffusion biased presence gradient provide sufficient mass transport toward top maintain supply neutrals for feeding plasma. To reach necessary timescales add MD, utilized novel combination collective variable~-driven hyperdynamics acceleration coupling finite element mesh. our simulations, observed self-diffusion on surfaces, continuous replenishment particle-emitting nanotips. This mechanism implies need reduce rate devices are susceptible arcs. Finding suitable alloys or treatments hinder could guide design future devices, greatly improve their efficiency.