Bond polarons and high-Tc superconductivity in single layer La_(2-x)Sr_xCuO_4: normal state currents and pairing

TL;DR

This paper introduces the concept of bond polarons as phonon-coupled entities linking CuO_2 layers in high-Tc superconductors, emphasizing their role in phase coherence and superconductivity, largely independent of doping levels.

Contribution

It proposes the bond polaron as a key factor in high-Tc superconductivity, offering insights into interlayer coupling and phase coherence beyond doping dependence.

Findings

Bond polarons facilitate interlayer coupling in high-Tc materials.

Linkage via bond polarons is less dependent on hole doping levels.

Analysis applies mainly to single-layered cuprates, with implications for multilayer systems.

Abstract

We use the term "bond polaron" for a phonon coupled entity which makes the link between neighboring conductive CuO_2 layers in high-Tc superconductive materials. The link is essential for the superconductivity which requires a long range phase coherence in addition to pairing of carriers. The linkage features studied point to a process which is less dependent on the doped hole density implanted as x in the solid solution. The analysis applies to single layered materials mostly but may help understand multilayer ones as well.