Accessing electronic entanglement via photo-assisted two-electron tomography
Abstract
Witnessing entanglement between electrons propagating in quantum circuits requires accessing their two-electron coherences, which encode the two-particle quantum correlations generated by Coulomb interactions. Yet, experimental reconstruction of two-electron coherence remains a major challenge. We introduce photo-assisted two-electron tomography, a quantum coherence reconstruction protocol from dc-currents and time-averaged current correlations, routinely measured in electron quantum optics experiments. Driving an energy filter with a small rf tone encodes off-diagonal coherences in the frequency domain into the dc-current response, enabling single-electron tomography without resorting to current-noise measurements. Extending it to two channels, current correlations after two photo-assisted filters reconstruct the two-electron Wigner distribution and isolate its irreducible two-body part. When applied to Coulomb-coupled quantum Hall edge channels, the protocol reveals interaction-induced energy entanglement. Signatures of this entanglement are visible through the violation of an entanglement witness based on Cauchy-Schwarz inequalities, as well as Wigner function negativities, which remain resolved above the thermal background for realistic device parameters. A generalized Franson geometry further extends the approach to intra-channel two-electron coherences. This opens a direct pathway to detect and characterize electronic entanglement in ballistic quantum circuits.
Related
- Quantum tomography at the Electron-Ion Collider
- Sample-Efficient Tomography of a Class of Mixed States with Extensive Entanglement and Magic
- Generation of entanglement statistics with a large-scale integrated photonic-electronic circuit
- Electron state tomography from quasiparticle interference maps
- Chromium-and Monolayer Graphene-Based Coating for THz-Assisted Atom Probe Tomography of Sol-Gel Silica Specimens
BibTeX
@misc{paulet2026accessing,
title = {{Accessing electronic entanglement via photo-assisted two-electron tomography}},
author = {M. Paulet and G. Rebora and M. Bienioszek and G. Ménard and G. Fève and A. Feller and P. Degiovanni},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.12286},
eprint = {2610.12286},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.12286},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Accessing electronic entanglement via photo-assisted two-electron tomography
AU - M. Paulet
AU - G. Rebora
AU - M. Bienioszek
AU - G. Ménard
AU - G. Fève
AU - A. Feller
AU - P. Degiovanni
PY - 2026
DA - 2026/10/08
PB - arXiv
DO - 10.48550/arxiv.2610.12286
UR - https://arxiv.org/abs/2610.12286
AB - Witnessing entanglement between electrons propagating in quantum circuits requires accessing their two-electron coherences, which encode the two-particle quantum correlations generated by Coulomb interactions. Yet, experimental reconstruction of two-electron coherence remains a major challenge. We introduce photo-assisted two-electron tomography, a quantum coherence reconstruction protocol from dc-currents and time-averaged current correlations, routinely measured in electron quantum optics experiments. Driving an energy filter with a small rf tone encodes off-diagonal coherences in the frequency domain into the dc-current response, enabling single-electron tomography without resorting to current-noise measurements. Extending it to two channels, current correlations after two photo-assisted filters reconstruct the two-electron Wigner distribution and isolate its irreducible two-body part. When applied to Coulomb-coupled quantum Hall edge channels, the protocol reveals interaction-induced energy entanglement. Signatures of this entanglement are visible through the violation of an entanglement witness based on Cauchy-Schwarz inequalities, as well as Wigner function negativities, which remain resolved above the thermal background for realistic device parameters. A generalized Franson geometry further extends the approach to intra-channel two-electron coherences. This opens a direct pathway to detect and characterize electronic entanglement in ballistic quantum circuits.
ER -