Inhomogeneous charge textures stabilized by electron-phonon interactions in the t-J model

TL;DR

This study investigates how electron-phonon interactions influence charge textures in the t-J model, revealing stabilization of stripe and tile phases, effects of phonon modes, and their impact on pairing correlations.

Contribution

It provides new insights into how diagonal and off-diagonal electron-phonon couplings affect charge inhomogeneities and pairing in the t-J model.

Findings

Charge stripes stabilized by half-breathing modes.

Tiles arise from extended breathing modes.

Moderate electron-phonon interactions coexist with D-wave pairing.

Abstract

We study the effect of diagonal and off-diagonal electron-phonon coupling in the ground state properties of the t-J model. Adiabatic and quantum phonons are considered using Lanczos techniques. Charge tiles and stripe phases with mobile holes (localized holes) are observed at intermediate (large) values of the diagonal electron-phonon coupling. The stripes are stabilized by half-breathing modes, while the tiles arise due to the development of extended breathing modes. Off-diagonal terms destabilize the charge inhomogeneous structures with mobile holes by renormalizing the diagonal coupling but do not produce new phases. Buckling modes are also studied and they seem to induce a gradual phase separation between hole rich and hole poor regions. The pairing correlations are strongly suppressed when the holes are localized. However, in charge inhomogeneous states with mobile holes no dramatic changes, compared with the uniform state, are observed in the pairing correlations indicating that D-wave pairing and moderate electron-phonon interactions can coexist.