Julien Barrier

My group studies how electron-electron interactions shape quantum matter in low dimensions, using electronic transport in graphene-based heterostructures.

We are looking for PhD students and postdocs. See how to apply or get in touch.

Max Planck Research Group Leader (W2)
Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, 70569 Stuttgart, Germany
j.barrier@fkf.mpg.de  ·  +49 711 689-1775

CV (pdf)  ·  Google Scholar  ·  ORCID  ·  Web of Science  ·  arXiv  ·  Awards & Funding

Research

• One-dimensional channels: ballistic channels along twist domain walls in bilayer graphene, with tunable interactions
• Coulomb screening: in-situ control of interaction strength in van der Waals heterostructures
• Josephson junctions: superconducting correlations in one-dimensional channels

Selected publications

1. J. Barrier, L. Peng, C. De Beule, S. Xu, V. I. Fal’ko, K. Watanabe, T. Taniguchi, A. K. Geim, S. Adam, and A. I. Berdyugin, Coulomb Screening of Superconductivity in Magic-Angle Twisted Bilayer Graphene, Physical Review X 16, 031040 (2026). [arXiv:2412.01577] [DOI]
2. D. Domaretskiy, Z. Wu, V. H. Nguyen, N. Hayward, I. Babich, X. Li, E. Nguyen, J. Barrier, K. Indykiewicz, W. Wang, R. V. Gorbachev, N. Xin, K. Watanabe, T. Taniguchi, L. Hague, V. I. Fal’ko, I. V. Grigorieva, L. A. Ponomarenko, A. I. Berdyugin, and A. K. Geim, Proximity Screening Greatly Enhances Electronic Quality of Graphene, Nature 644, 646 (2025). [arXiv:2507.21997] [DOI]
3. K. Nowakowski, H. Agarwal, S. Slizovskiy, R. Smeyers, X. Wang, Z. Zheng, J. Barrier, D. Barcons Ruiz, G. Li, R. Bertini, M. Ceccanti, I. Torre, B. Jorissen, A. Reserbat-Plantey, K. Watanabe, T. Taniguchi, L. Covaci, M. V. Milosevic, V. Fal’ko, P. Jarillo-Herrero, K. Kumar, and F. H. L. Koppens, Single-Photon Detection Enabled by Negative Differential Conductivity in Moiré Superlattices, Science 389, 644 (2025). [arXiv:2505.13637] [DOI]
4. J. Barrier, M. Kim, R. Krishna Kumar, N. Xin, P. Kumaravadivel, L. Hague, E. Nguyen, A. I. Berdyugin, C. Moulsdale, V. V. Enaldiev, J. R. Prance, F. H. L. Koppens, R. V. Gorbachev, K. Watanabe, T. Taniguchi, L. I. Glazman, I. V. Grigorieva, V. I. Fal’ko, and A. K. Geim, One-Dimensional Proximity Superconductivity in the Quantum Hall Regime, Nature 628, 741 (2024). [arXiv:2402.14451] [DOI] [PDF]

All publications

News

• Nov 2026  I was interviewed by french radio France Culture on our screening paper - (podcast)
• Oct 2026  Bandwidth-limited critical currents in electrically tunable moiré bands published in Nano Letters (publications)
• Oct 2026  Released mesoscopy, an open-source GUI for mesoscopic physics experiments (announcement)
• Sep 2026  Coulomb screening of superconductivity in magic-angle graphene (press release)

All news and posts

Affiliation

Disclaimer: all views and opinions expressed on this website are solely my own and do not necessarily reflect those of any past or present employer, funder or collaborator.