Subnanosecond single electron source in the time-domain

TL;DR

This paper reports the development of a fast, on-demand single electron source using a quantum dot, capable of emitting electrons in subnanosecond timescales, with detailed experimental and theoretical analysis.

Contribution

It introduces a novel single electron source with tunable emission timing and provides experimental validation and theoretical modeling of its operation.

Findings

Single electron emission achieved in 100 ps to 10 ns range.

Real-time detection with 0.5 ns resolution demonstrated.

Good agreement between experiment and scattering theory simulations.

Abstract

We describe here the realization of a single electron source similar to single photon sources in optics. On-demand single electron injection is obtained using a quantum dot connected to the conductor via a tunnel barrier of variable transmission (quantum point contact). Electron emission is triggered by a sudden change of the dot potential which brings a single energy level above the Fermi energy in the conductor. A single charge is emitted on an average time ranging from 100 ps to 10 ns ultimately determined by the barrier transparency and the dot charging energy. The average single electron emission process is recorded with a 0.5 ns time resolution using a real-time fast acquisition card. Single electron signals are compared tosimulation based on scattering theory approach adapted for finite excitation energies.