Fermiology and the Candidate Chiral Superconductor in Rhombohedral Tetralayer Graphene
7 affiliations
- 1Department of Physics , Stanford University , Stanford , CA 94305
- 2Department of Physics , Princeton University , Princeton , New Jersey 08544 , USA
- 3Stanford Institute for Materials and Energy Sciences , SLAC National Accelerator Laboratory , Menlo Park , CA 94025
- 4Research Center for Electronic and Optical Materials , National Institute for Materials Science , 1-1 Namiki , Tsukuba 305-0044 , Japan
- 5Research Center for Materials Nanoarchitectonics , National Institute for Materials Science , 1-1 Namiki , Tsukuba 305-0044 , Japan
- 6Department of Physics , University of Texas at Dallas , Richardson , Texas 75080 , USA
- 7Department of Physics , University of California at San Diego , La Jolla , California 92093 , USA
Abstract
Chiral superconductivity, in which the phase of the superconducting order parameter winds in momentum space, has long been sought for its close link to topological superconductivity. Recent work reported a superconductor in rhombohedral multilayer graphene emerging from a time-reversal symmetry broken normal state, suggesting that it could be a chiral superconductor. However, the possibility of chirality depends on the symmetry and structure of the normal-state Fermi surface, which have not been directly measured. Here we measure quantum oscillations in rhombohedral tetralayer graphene over a broad range of the phase diagram, including the superconducting region. At densities well above the onset of superconductivity, we reproduce previously-reported oscillations consistent with a spin- and valley-polarized quarter metal with a single simply-connected Fermi pocket. As the carrier density is reduced, we find a transition to a complex "multitone" state that persists through the superconducting region. This state's spectrum of quantum oscillations is incompatible with a simply-connected quarter metal. The next-simplest candidate normal states suggested by our microscopic modeling (fully-polarized annular, nematic, and three-pocket states) are inconsistent with our measurements, albeit difficult to rule out entirely. The normal state is thus seen to be richer than previously envisaged, reshaping the search for the superconducting mechanism and the possible chirality of the pairing channel.
Related
- Finite-Momentum Pairing and Superlattice Superconductivity in Valley-Imbalanced Rhombohedral Graphene
- Emerging network model in a twisted monolayer-rhombohedral graphene
- Quantum Oscillations across Hole Crystallization in Rhombohedral Graphene
- Anomalous Hall Response and Real-Space Current Correlations in Rhombohedral Graphene
- Rhombohedral Multilayer Graphene as a p-Wave Magnet
BibTeX
@misc{kalantre2026fermiology,
title = {{Fermiology and the Candidate Chiral Superconductor in Rhombohedral Tetralayer Graphene}},
author = {Sandesh S. Kalantre and Ben Hodder Alexander and Julian May-Mann and Jonah Herzog-Arbeitman and Marisa Hocking and Qingrui Cao and Kenji Watanabe and Takashi Taniguchi and David Goldhaber‐Gordon and Andrew J. Mannix and Trithep Devakul and Yves H. Kwan and Daniel E. Parker and Aaron L. Sharpe},
howpublished = {arXiv (Cornell University)},
year = {2026},
month = jun,
doi = {10.48550/arxiv.2606.05356},
url = {https://arxiv.org/abs/2606.05356},
note = {CC BY},
}
RIS
TY - UNPB
TI - Fermiology and the Candidate Chiral Superconductor in Rhombohedral Tetralayer Graphene
AU - Sandesh S. Kalantre
AU - Ben Hodder Alexander
AU - Julian May-Mann
AU - Jonah Herzog-Arbeitman
AU - Marisa Hocking
AU - Qingrui Cao
AU - Kenji Watanabe
AU - Takashi Taniguchi
AU - David Goldhaber‐Gordon
AU - Andrew J. Mannix
AU - Trithep Devakul
AU - Yves H. Kwan
AU - Daniel E. Parker
AU - Aaron L. Sharpe
PY - 2026
DA - 2026/06/03
PB - arXiv (Cornell University)
DO - 10.48550/arxiv.2606.05356
UR - https://arxiv.org/abs/2606.05356
AB - Chiral superconductivity, in which the phase of the superconducting order parameter winds in momentum space, has long been sought for its close link to topological superconductivity. Recent work reported a superconductor in rhombohedral multilayer graphene emerging from a time-reversal symmetry broken normal state, suggesting that it could be a chiral superconductor. However, the possibility of chirality depends on the symmetry and structure of the normal-state Fermi surface, which have not been directly measured. Here we measure quantum oscillations in rhombohedral tetralayer graphene over a broad range of the phase diagram, including the superconducting region. At densities well above the onset of superconductivity, we reproduce previously-reported oscillations consistent with a spin- and valley-polarized quarter metal with a single simply-connected Fermi pocket. As the carrier density is reduced, we find a transition to a complex "multitone" state that persists through the superconducting region. This state's spectrum of quantum oscillations is incompatible with a simply-connected quarter metal. The next-simplest candidate normal states suggested by our microscopic modeling (fully-polarized annular, nematic, and three-pocket states) are inconsistent with our measurements, albeit difficult to rule out entirely. The normal state is thus seen to be richer than previously envisaged, reshaping the search for the superconducting mechanism and the possible chirality of the pairing channel.
SN - 2331-8422
ER -