English

Stripe antiferromagnetism and chiral superconductivity in tWSe$_2$

Strongly Correlated Electrons 2026-01-29 v1 Materials Science Superconductivity

Abstract

The layer-dependent Hamiltonians of parallel-stacked MoTe2_2 and WSe2_2 homobilayer moir\'e materials are topologically non-trivial, both in real space and in momentum space, and have been shown to support integer and fractional quantum anomalous Hall states, as well as antiferromagnetic and superconducting states. Here, we address the interplay between the antiferromagnetic and superconducting states observed in tWSe2_2 when the Fermi level is close to its MM-point van Hove singularity and the displacement field is small. We combine DFT with path-integrals to construct a minimal moir\'e band model that accounts for lattice relaxation along the cc-axis and perform Hartree-Fock calculations to identify competing charge and spin ordered states. For tWSe2_2 at θ=2.7\theta=2.7^\circ and θ=3.65\theta=3.65^\circ, we find that a layer antiferromagnet (AFM), a stripe spin-density-wave (SDW), and the ferromagnetic Chern insulator (FM) are the primary candidates for the ground state at zero displacement field, and argue that antiferromagnetic spin interactions on the next neighbor bond J2J_2 can induce a time-reversal symmetry breaking chiral superconducting state.

Keywords

Cite

@article{arxiv.2601.20836,
  title  = {Stripe antiferromagnetism and chiral superconductivity in tWSe$_2$},
  author = {Erekle Jmukhadze and Sam Olin and Allan H. MacDonald and Wei-Cheng Lee},
  journal= {arXiv preprint arXiv:2601.20836},
  year   = {2026}
}

Comments

10 pages, 5 figures