2025/05/16 by Emmanouil K. Kokkinis, Andrey V. Chubukov, Kokkinis, Emmanouil K. +1 · 2 citations
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Superconductivity in MgB2 and Alloys
paper · pdf · doi:10.1038/s41467-025-67835-w
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 in a weak pseudogap regime, which we justify. 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 in a weak pseudogap regime thermal fluctuations almost cancel out in the gap equation. We favorably compare our results with recent ARPES studies. The authors study pseudogap in electron-doped cuprates by computing the fermionic self energy beyond Eliashberg approximation. They show that recent experiments are consistent with the idea that pseudogap behavior is caused by thermal antiferromagnetic fluctuations with no Fermi-surface reconstruction.