The fate of s± superconductivity in the bilayer nickelate La3Ni2O7
Abstract
Motivated by the recent measurement of high-temperature superconductivity in the bilayer nickelate system La3Ni2O7 in the bulk as well as thin film samples, we seek to understand the role of the interlayer coupling in this system in dictating the pairing symmetry. Many proposals posit the existence of an s± superconducting phase in close competition with the mroe conventional cuprate-like d-wave state in both weak- and strong-coupling theories. However, at least in the latter, the effects of Coulomb repulsion and the double occupancy constraint have been largely neglected. In this manuscript, we propose a mean-field fractionalization treatment that captures the full SU(2) particle-hole symmetry of the t-J model at half-filling, and show how a systematic treatment of this new symmetry leads to an added Coulomb pseudopotential constraint - one that is absent in the usual U(1) treatment. We then apply this new fractionalization scheme to a simplified bilayer t-J model of La3Ni2O7, showing how the Coulomb pseudopotential suppresses the existence of s± symmetry in favor of d-wave pairing.
Related
- Observation of superconductivity-induced leading-edge gap in a bilayer nickelate
- Spectroscopic evidence of competing diagonal spin interactions and spin disproportionation in the bilayer nickelate La 3 Ni 2 O 7
- Direct imaging of the Ni eg hole orbitals in the bilayer nickelate La2SmNi2O7
- Electronic theory for scanning tunneling microscopy spectra in bilayer nickelate thin films
- Selective suppression of electronic orders via interlayer coupling in superconducting bilayer nickelate thin films
BibTeX
@misc{roy2026fate,
title = {{The fate of $s_\pm$ superconductivity in the bilayer nickelate La$_3$Ni$_2$O$_7$}},
author = {Kaustubh Roy and Piers Coleman},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.35814},
eprint = {2610.35814},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.35814},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The fate of s_± superconductivity in the bilayer nickelate La_3Ni_2O_7
AU - Kaustubh Roy
AU - Piers Coleman
PY - 2026
DA - 2026/10/26
PB - arXiv
DO - 10.48550/arxiv.2610.35814
UR - https://arxiv.org/abs/2610.35814
AB - Motivated by the recent measurement of high-temperature superconductivity in the bilayer nickelate system La_3Ni_2O_7 in the bulk as well as thin film samples, we seek to understand the role of the interlayer coupling in this system in dictating the pairing symmetry. Many proposals posit the existence of an s_± superconducting phase in close competition with the mroe conventional cuprate-like d-wave state in both weak- and strong-coupling theories. However, at least in the latter, the effects of Coulomb repulsion and the double occupancy constraint have been largely neglected. In this manuscript, we propose a mean-field fractionalization treatment that captures the full SU(2) particle-hole symmetry of the t-J model at half-filling, and show how a systematic treatment of this new symmetry leads to an added Coulomb pseudopotential constraint - one that is absent in the usual U(1) treatment. We then apply this new fractionalization scheme to a simplified bilayer t-J model of La_3Ni_2O_7, showing how the Coulomb pseudopotential suppresses the existence of s_± symmetry in favor of d-wave pairing.
ER -