Quantum phase fluctuations quench chiral superconductivity in twisted overdoped cuprate bilayers
Abstract
Twisted cuprate bilayers have been proposed to host chiral superconductivity at temperatures comparable to their large pairing scale, yet experimental signatures of broken time-reversal symmetry remain unclear. We show that quantum phase fluctuations strongly suppress chiral order in twisted overdoped cuprate bilayers despite robust intralayer pairing. At a 45∘ twist, we analytically demonstrate that the chiral transition temperature obeys Tχ∝ t4 when the single-electron interlayer tunneling amplitude t is weak. This collapse originates from competition between the small Josephson energy scale supporting chirality and the temperature-dependent collective zero-point energy. Chirality consequently survives only in a narrow angular window at ultralow temperatures, with relative-phase plasma softening above the chiral transition. A distinct transport signature arising from the quantum phase fluctuations is a pronounced low-temperature enhancement of the critical current near a magic angle. These findings separate pairing and chiral ordering scales and offer a possible explanation for the difficulty of observing robust chiral superconductivity in twisted cuprates.
Related
- Persistence of vortexlike phase fluctuations in underdoped to heavily overdoped cuprates
- Twisted Kagome Bilayers: High-Order Van Hove Singularities, Sublattice Interference, Magic Angles, and Possible Topology
- Topological properties and gap structure of the paired state in twisted TMD bilayers within a two-band effective model
- Symmetry-Based Design Rules for Second-Harmonic Generation in Stacked and Twisted MoS2 Bilayers
- Collective phase modes in twisted d-wave superconducting bilayers
BibTeX
@misc{shi2026quantum,
title = {{Quantum phase fluctuations quench chiral superconductivity in twisted overdoped cuprate bilayers}},
author = {Yin Shi and Mengxian Zhao and Fei Yang and Miao Liu and Sheng Meng},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2607.00630},
eprint = {2607.00630},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.00630},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Quantum phase fluctuations quench chiral superconductivity in twisted overdoped cuprate bilayers
AU - Yin Shi
AU - Mengxian Zhao
AU - Fei Yang
AU - Miao Liu
AU - Sheng Meng
PY - 2026
DA - 2026/10/31
PB - arXiv
DO - 10.48550/arxiv.2607.00630
UR - https://arxiv.org/abs/2607.00630
AB - Twisted cuprate bilayers have been proposed to host chiral superconductivity at temperatures comparable to their large pairing scale, yet experimental signatures of broken time-reversal symmetry remain unclear. We show that quantum phase fluctuations strongly suppress chiral order in twisted overdoped cuprate bilayers despite robust intralayer pairing. At a 45^∘ twist, we analytically demonstrate that the chiral transition temperature obeys T_χ∝ t^4 when the single-electron interlayer tunneling amplitude t is weak. This collapse originates from competition between the small Josephson energy scale supporting chirality and the temperature-dependent collective zero-point energy. Chirality consequently survives only in a narrow angular window at ultralow temperatures, with relative-phase plasma softening above the chiral transition. A distinct transport signature arising from the quantum phase fluctuations is a pronounced low-temperature enhancement of the critical current near a magic angle. These findings separate pairing and chiral ordering scales and offer a possible explanation for the difficulty of observing robust chiral superconductivity in twisted cuprates.
ER -