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Abstract We study the ground state properties of the Hubbard model on three-leg triangular cylinders using large-scale density-matrix renormalization group simulations. At half-filling, we identify an intermediate gapless spin liquid phase, which has one gapless spin mode and algebraic spināspin correlations but exponential decay scalar chiralāchiral correlations, between a metallic phase at weak coupling and Mott insulating dimer phase at strong interaction. Upon light doping the gapless spin liquid, the system exhibits power-law charge-density-wave (CDW) correlations but short-range single-particle, spināspin, and chiralāchiral correlations. Similar to CDW correlations, the superconducting correlations also decay in power-law but oscillate in sign as a function of distance, which is consistent with the striped pair-density wave. When further doping the gapless spin liquid phase or doping the dimer order phase, another phase takes over, which has similar CDW correlations but all other correlations decay exponentially.
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This content will become publicly available on August 13, 2026
Nodal pair density waves from a quarter-metal in crystalline graphene multilayers
Crystalline graphene heterostructures, namely, Bernal bilayer graphene (BBLG) and rhombohedral trilayer graphene (RTLG), for example, subject to perpendicular electric displacement fields, display a rich confluence of competing orders, resulting in a valley-degenerate, spin-polarized half-metal at moderate doping, and a spin- and valley-polarized (nondegenerate) quarter-metal at lower doping. Here we show that such a quarter-metal can be susceptible toward the nucleation of a unique spin- and valley-polarized superconducting ground state, accommodating odd-parity (dominantly š wave in BBLG and š wave in RTLG) interlayer Cooper pairs that break the translational symmetry, giving rise to a Kekule (in BBLG) or columnar (in RTLG) pair density wave. Due to the trigonal warping in the normal state, the superconducting ground state produces threefold rotationally symmetric isolated Fermi rings of normal fermions, which can manifest via linear in temperature scaling of the specific heat. We present scaling of the zero-temperature pairing amplitude and the transition temperature of such pair density wave in the presence of trigonally warped disconnected, annular, and simply connected Fermi rings in the normal state, subject to an effective attractive interaction within a mean-field approximation.
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- Award ID(s):
- 2238679
- PAR ID:
- 10655781
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review B
- Volume:
- 112
- Issue:
- 8
- ISSN:
- 2469-9950
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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