Multimode electron-phonon interactions in the 2-dimensional t-J-Holstein model

TL;DR

This paper explores how dynamic in-plane phonons influence polaron formation, spin correlations, and potential stripe phases in the 2D t-J model relevant to high-temperature cuprate superconductors.

Contribution

It demonstrates the impact of multi-phonon modes on hole localization and magnetic correlations, highlighting the role of dynamic phonons in stabilizing inhomogeneous phases.

Findings

Evidence for hole self-localization due to phonons

Increased short-range antiferromagnetic correlations

Persistence of effects with all in-plane oxygen modes included

Abstract

Polaronic effects are investigated in the two dimensional t--J model (describing Cu spins and holes of the planes in high-$T_c$ cuprates) in the presence of in-plane dynamic oxygen breathing modes. We focus on the effect of dynamic multi-phonon modes. Spin and charge structure factors are computed. We found evidence for self-localisation of the holes and {\it increased} short range antiferromagnetic spin-spin correlations between the remaining spins. This effect persists when all the in-plane oxygen vibration degrees of freedom are taken into account. This suggests that dynamic phonons could play a key role in stabilizing inhomogeneous stripe phases or domain wall structures.