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arXiv · 2412.15789

Coulomb sensing of single ballistic electrons

J. D. Fletcher·W. Park·P. See·J. P. Griffiths·G. A. C. Jones·I. Farrer·D. A. Ritchie·H. -S. Sim·M. Kataoka
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Abstract

While ballistic electrons are a key tool for applications in sensing and flying qubits, sub-nanosecond propagation times and complicated interactions make control of ballistic single electrons challenging. Recent experiments have revealed Coulomb collisions of counterpropagating electrons in a beam splitter, giving time resolved control of interactions between single electrons. Here we use remote Coulomb interactions to demonstrate a scheme for sensing single ballistic electrons. We show that interactions are highly controllable via electron energy and emission timing. We use a weakly-coupled `sensing' regime to characterise the nanoscale potential landscape of the beam splitter and the strength of the Coulomb interaction, and show multi-electron sensing with picosecond resolution.

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J. D. Fletcher, W. Park, P. See, J. P. Griffiths, G. A. C. Jones, I. Farrer, D. A. Ritchie, H. -S. Sim, M. Kataoka. 2024-12-20. Coulomb sensing of single ballistic electrons. https://arxiv.org/abs/2412.15789

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