Decrease of d-wave pairing strength in spite of the persistence of magnetic excitations in the overdoped Hubbard model

Abstract

Evidence for the presence of high energy magnetic excitations in overdoped La${}_{2-x}$Sr${}_x$CuO${}_4$ (LSCO) has raised questions regarding the role of spin-fluctuations in the pairing mechanism. If they remain present in overdoped LSCO, why does $T_c$ decrease in this doping regime? Here, using results for the dynamic spin susceptibility $\mathrm{Im}\chi (q,\omega )$ obtained from a determinantal quantum Monte Carlo (DQMC) calculation for the Hubbard model we address this question. We find that while high energy magnetic excitations persist in the overdoped regime, they lack the momentum to scatter pairs between the anti-nodal regions. It is the decrease in the spectral weight at large momentum transfer, not observed by resonant inelastic X-ray scattering (RIXS), which leads to a reduction in the $d$-wave spin-fluctuation pairing strength.

References in corpus (6)

• Disappearance of antiferromagnetic spin excitations in over-doped La${}_{2-x}$Sr${}_x$CuO${}_4$
• The Persistence of High-Frequency Spin Fluctuations in Overdoped La${}_{2-x}$Sr${}_x$CuO${}_4$ ($x$=0.22)
• Analytical continuation of imaginary axis data using maximum entropy
• Doping dependence of the magnetic excitations in La${}_{2-x}$Sr${}_x$CuO${}_4$
• High-energy magnetic excitations in overdoped La${}_{2-x}$Sr${}_x$CuO${}_4$ studied by neutron and resonant inelastic X-ray scattering
• Spin Susceptibility Representation of the Pairing Interaction for the two-dimensional Hubbard Model

Cited by in corpus (2)

• Doping dependence of ordered phases and emergent quasiparticles in the doped Hubbard-Holstein model
• Signatures of pairing in the magnetic excitation spectrum of strongly correlated ladders