English

Monte Carlo study of the pseudogap and superconductivity emerging from quantum magnetic fluctuations

Strongly Correlated Electrons 2022-05-16 v3 Superconductivity

Abstract

The origin of the pseudogap behavior, found in many high-TcT_c superconductors, remains one of the greatest puzzles in condensed matter physics. One possible mechanism is fermionic incoherence, which near a quantum critical point allows pair formation but suppresses superconductivity. Employing quantum Monte Carlo simulations of a model of itinerant fermions coupled to ferromagnetic spin fluctuations, represented by a quantum rotor, we report numerical evidence of pseudogap behavior, emerging from pairing fluctuations in a quantum-critical non-Fermi liquid. Specifically, we observe enhanced pairing fluctuations and a partial gap opening in the fermionic spectrum. However, the system remains non-superconducting until reaching a much lower temperature. In the pseudogap regime the system displays a "gap-filling" rather than "gap-closing" behavior, consistent with experimental observations. Our results provide the first unambiguous lattice model realization of a pseudogap state in a strongly correlated system, driven by superconducting fluctuations.

Keywords

Cite

@article{arxiv.2105.03639,
  title  = {Monte Carlo study of the pseudogap and superconductivity emerging from quantum magnetic fluctuations},
  author = {Weilun Jiang and Yuzhi Liu and Avraham Klein and Yuxuan Wang and Kai Sun and Andrey V. Chubukov and Zi Yang Meng},
  journal= {arXiv preprint arXiv:2105.03639},
  year   = {2022}
}

Comments

9+14 pages, 4+13 figures