Electron quantum optics : partitioning electrons one by one

TL;DR

This paper demonstrates a quantum optics experiment with electrons, using a single-electron source and a beam-splitter to measure and analyze electron/hole pairs and their quantum correlations.

Contribution

It introduces a method to directly count elementary electronic excitations at the single-charge level using an electronic HBT setup with an on-demand emitter.

Findings

Observed antibunching of emitted low-energy excitations with thermal Fermi sea electrons.

Probed the energy distribution of emitted electron wave-packets.

Showed suppression of partition noise due to antibunching effects.

Abstract

We have realized a quantum optics like Hanbury Brown and Twiss (HBT) experiment by partitioning, on an electronic beam-splitter, single elementary electronic excitations produced one by one by an on-demand emitter. We show that the measurement of the output currents correlations in the HBT geometry provides a direct counting, at the single charge level, of the elementary excitations (electron/hole pairs) generated by the emitter at each cycle. We observe the antibunching of low energy excitations emitted by the source with thermal excitations of the Fermi sea already present in the input leads of the splitter, which suppresses their contribution to the partition noise. This effect is used to probe the energy distribution of the emitted wave-packets.