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arXiv · 2505.11727

Pseudogap in electron-doped cuprates: thermal precursor to magnetism

Emmanouil K. Kokkinis·Andrey V. Chubukov
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Abstract

We study pseudogap behavior in a metal near an antiferromagnetic instability and apply the results to electron-doped cuprates. We associate pseudogap behavior with thermal magnetic fluctuations and compute the fermionic self-energy along the Fermi surface beyond Eliashberg approximation. We analyze the spectral function as a function of frequency (energy distribution curves, EDC) and momentum (momentum distribution curves, MDC). We show that the EDC display pseudogap behavior with peaks at a finite frequency at all momenta. On the other hand, MDC peaks disperse within the pseudogap, ending at a gossamer Fermi surface. We analyze magnetically-mediated superconductivity and show that thermal fluctuations almost cancel out in the gap equation, even when the self-energy is obtained beyond the Eliashberg approximation. We favorably compare our results with recent ARPES study [K-J Xu et al, Nat. Phys. 19, 1834-1840 (2023)].

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Emmanouil K. Kokkinis, Andrey V. Chubukov. 2025-05-16. Pseudogap in electron-doped cuprates: thermal precursor to magnetism. https://doi.org/10.1038/s41467-025-67835-w

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