On possible superconductivity in the doped ladder compound La_(1-x)Sr_xCuO_2.5

TL;DR

This paper explores the potential for superconductivity in doped La_(1-x)Sr_xCuO_2.5, a ladder compound, using a spin fluctuation model and solving coupled gap equations to identify possible superconducting states.

Contribution

It provides a theoretical analysis of superconductivity in La_(1-x)Sr_xCuO_2.5 based on a spin fluctuation mechanism, considering doping effects and ladder band structures.

Findings

Superconducting solutions exist across various doping levels.

Pairing potential peaks at  in the ladder direction.

Relevance of solutions to experimental materials discussed.

Abstract

LaCuO_2.5 is a system of coupled, two-chain, cuprate ladders which may be doped systematically by Sr substitution. Motivated by the recent synthesis of single crystals, we investigate theoretically the possibility of superconductivity in this compound. We use a model of spin fluctuation-mediated superconductivity, where the pairing potential is strongly peaked at \pi in the ladder direction. We solve the coupled gap equations on the bonding and antibonding ladder bands to find superconducting solutions across the range of doping, and discuss their relevance to the real material.