Pair Density Waves in coupled doped two-leg Ladders

TL;DR

This paper investigates charge order modulations in coupled doped two-leg ladders using DMRG and mean-field methods, revealing pair density waves consistent with experiments and predicting a potential new modulation period.

Contribution

It introduces a detailed theoretical analysis of charge order patterns and pair density waves in coupled ladders, extending understanding of experimental observations in cuprate materials.

Findings

Charge order modulations of periods 3, 4, and 5 identified.

Pair density waves linked to strong electronic correlations.

Prediction of a 4-period modulation not yet observed experimentally.

Abstract

Motivated by Resonant X-ray scattering experiments in cuprate ladder materials showing charge order modulation of period $\lambda=3$ and 5 at specific hole densities, we investigate models involving the electronic t-J ladders and bosonic chains coupled via screened Coulomb repulsion. Extensive density matrix renormalization group calculations applied to the ladders/chains supplemented by a self-consistent mean-field treatment of the inter-ladder/chain coupling provide quantitative estimates of the charge order for $\lambda=3,4$ and 5. As previously proposed, such patterns correspond to the emergence of pair density waves which stem from the strong electronic correlations. We comment on the existence of a $\lambda=4$ modulation not seen so far in experiment.