Displacement Current Staircase in Mechanical Single-Electron Turnstiles

Abstract

Coulomb-blockade-based displacement current staircases are observed in the displacement current–voltage characteristics of double barrier tunneling junctions with a vibrating probe. Displacement current flows periodically in accordance with the mechanical oscillation of the reservoir and is separated from the tunneling current using a two-phase lock-in amplifier. The theoretical displacement current staircase is successfully fitted to the measurement. This displacement current staircase demonstrates the mechanical single-electron turnstiles in which the quantized number of electrons on the gold dots alternates periodically with the mechanical oscillation.