Competition Between Stripes and Pairing in a t-t'-J Model

TL;DR

This paper investigates how introducing a next-near-neighbor hopping term t' in a t-J ladder model influences stripe formation and pairing correlations, finding that positive t' suppresses stripes and enhances pairing.

Contribution

It demonstrates that a diagonal hopping term t' can control stripe formation and pairing, providing new insights into the interplay between these phenomena in ladder models.

Findings

Positive t' suppresses stripe formation and enhances pairing.

Negative t' promotes stripe stability and quasiparticle behavior.

Results are shown for 4- and 6-leg ladder systems.

Abstract

As the number of legs n of an n-leg, t-J ladder increases, density matrix renormalization group calculations have shown that the doped state tends to be characterized by a static array of domain walls and that pairing correlations are suppressed. Here we present results for a t-t'-J model in which a diagonal, single particle, next-near-neighbor hopping t' is introduced. We find that this can suppress the formation of stripes and, for t' positive, enhance the d_{x^2-y^2}-like pairing correlations. The effect of t' > 0 is to cause the stripes to evaporate into pairs and for t' < 0 to evaporate into quasi-particles. Results for n=4 and 6-leg ladders are discussed.