Magnetic electron-hole asymmetry in cuprates: a computational revisit

TL;DR

This study revisits the electron-hole asymmetry in cuprates' antiferromagnetism using various computational methods, finding that intrinsic asymmetry is minimal and that dopant effects significantly influence observed asymmetries.

Contribution

It demonstrates that intrinsic electron-hole asymmetry in cuprates is negligible and highlights the importance of dopant-induced effects in observed asymmetries.

Findings

No significant intrinsic electron-hole asymmetry across methods.

Dopant-induced local potentials influence asymmetry.

Defects enhance or suppress AFM depending on doping type.

Abstract

In this work, we revisit the electron-hole asymmetry of antiferromagnetism in cuprates by studying the three-band Emery model. Using parameters relevant to La$_2$CuO$_4$, we benchmark the anti-ferromagnetic response for a large range of dopings with variational Monte Carlo, determinant quantum Monte Carlo, constrained-path auxiliary-field quantum Monte Carlo, density-matrix embedding theory, and the Gutzwiller approximation. Across methods and accessible sizes/temperatures, we find no significant electron-hole asymmetry if we consider only Neel anti-ferronagnetic response and ignore other possible orders such as stripe state. This result is robust to a moderate oxygen-site repulsion $U_p$ and to parameter sets of Nd$_2$CuO$_4$. Incorporating dopant-induced local potentials reveals an extrinsic route to asymmetry: Cu-site defects enhance AFM on the electron-doped side, whereas O-site defects suppress it on the hole-doped side. These results indicate that dopant-driven effects make a non-negligible contribution to apparent electron-hole asymmetry in the general phase diagram of cuprates and should be included when analyzing competing orders in cuprates.