Influence of the incommensurability in $Sr_{14-x}Ca_xCu_{24}O_{41}$ family compounds

TL;DR

This study investigates how structural incommensurability affects the low-energy electronic properties of $Sr_{14-x}Ca_xCu_{24}O_{41}$ compounds, revealing its role in electron localization, dimer formation, and magnetic order.

Contribution

It provides ab-initio analysis of effective parameters showing the impact of structural modulation on low-energy physics in these compounds.

Findings

Structural modulation influences electron localization.

Modulation affects formation of dimers and magnetic order.

Key degree of freedom in low-energy properties.

Abstract

The present paper studies the influence of the structural modulation on the low energy physics of the $Sr_{14-x}Ca_xCu_{24}O_{41}$ oxides, using ab-initio determination of the on-site and nearest neighbor effective parameters. The structural modulations appears to be the key degree of freedom, responsible for the low energy properties, such as the electron localization, the formation of dimers in the $x=0$ compound or the anti-ferromagnetic order in the $x=13.6$ compound.