Coulomb-mediated antibunching of an electron pair surfing on sound

• Published in: Nature nanotechnology Vol. 18; no. 7; pp. 721 - 726
• Main Authors: Wang, Junliang, Edlbauer, Hermann, Richard, Aymeric, Ota, Shunsuke, Park, Wanki, Shim, Jeongmin, Ludwig, Arne, Wieck, Andreas D., Sim, Heung-Sun, Urdampilleta, Matias, Meunier, Tristan, Kodera, Tetsuo, Kaneko, Nobu-Hisa, Sellier, Hermann, Waintal, Xavier, Takada, Shintaro, Bäuerle, Christopher
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.07.2023; Nature Publishing Group
• Subjects: 639/766/25/3927; 639/766/483/2802; 639/925/927/1007; 639/925/927/481; Atoms & subatomic particles; Chemistry and Materials Science; Circuits; Condensed Matter; Flight; Materials Science; Nanotechnology; Nanotechnology and Microengineering; Optics; Photonics; Physics; Quantum computers; Quantum dots; Qubits (quantum computing); Scanning electron microscopy; Single electrons; Surface acoustic waves; Acoustics; Quantum information; Electronic devices; Qubits
• ISSN: 1748-3387; 1748-3395; 1748-3395
• DOI: 10.1038/s41565-023-01368-5

Electron flying qubits are envisioned as potential information links within a quantum computer, but also promise—like photonic approaches—to serve as self-standing quantum processing units. In contrast to their photonic counterparts, electron-quantum-optics implementations are subject to Coulomb interactions, which provide a direct route to entangle the orbital or spin degree of freedom. However, controlled interaction of flying electrons at the single-particle level has not yet been established experimentally. Here we report antibunching of a pair of single electrons that is synchronously shuttled through a circuit of coupled quantum rails by means of a surface acoustic wave. The in-flight partitioning process exhibits a reciprocal gating effect which allows us to ascribe the observed repulsion predominantly to Coulomb interaction. Our single-shot experiment marks an important milestone on the route to realize a controlled-phase gate for in-flight quantum manipulations. Collisions between two individual electrons in a quantum nanoelectronic circuit revealed a mutual interaction fully mediated by Coulomb repulsion—an essential building block for two-qubit logic implementations with flying electrons.