Abstract
Evidence for the presence of high-energy magnetic excitations in overdoped La2-xSrxCuO4 (LSCO) has raised questions regarding the role of spin fluctuations in the pairing mechanism. If they remain present in overdoped LSCO, why does Tc decrease in this doping regime? Here, using results for the dynamic spin susceptibility Imχ(q,ω) obtained from a determinantal quantum Monte Carlo 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 antinodal regions. It is the decrease in the spectral weight at large momentum transfer, not observed by resonant inelastic x-ray scattering, which leads to a reduction in the d-wave spin-fluctuation pairing strength.
| Original language | English |
|---|---|
| Article number | 020503 |
| Journal | Physical Review B |
| Volume | 96 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jul 17 2017 |
Funding
We acknowledge helpful discussions with Christian Mendl, Yvonne Kung, and Chunjing Jia. Computational work was performed on the Sherlock cluster at Stanford University. This work was supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under Contract No. DE-AC02-76SF00515. A portion of this research was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.