An On-Demand Coherent Single-Electron Source
Gwendal Fève, Adrien Mahé, Jean‐Marc Berroir, T. Kontos, Bernard Plaçais, D. C. Glattli, A. Cavanna, B. Etienne, Yong Wan Jin · Science · 2007
We report on the electron analog of the single-photon gun. On-demand single-electron injection in a quantum conductor was obtained using a quantum dot connected to the conductor via a tunnel barrier. Electron emission was triggered by the application of a potential step that compensated for the dot-charging energy. Depending on the barrier transparency, the quantum emission time ranged from 0.1 to 10 nanoseconds. The single-electron source should prove useful for the use of quantum bits in ballistic conductors. Additionally, periodic sequences of single-electron emission and absorption generate a quantized alternating current.