Many body effects on $c$- axis properties: out of plane coherence and bilayer splitting

TL;DR

This paper theoretically investigates how strong in-plane electronic correlations affect out-of-plane properties in layered cuprates, focusing on bilayer splitting and interlayer coherence, revealing temperature and doping dependencies.

Contribution

It introduces a Renormalization Group approach to analyze the impact of in-plane correlations on interlayer hopping and bilayer splitting in high-Tc cuprates.

Findings

Bilayer splitting depends strongly on temperature and doping.

Strong correlations suppress quasiparticle weight and interlayer hopping.

Bilayer splitting can vanish near Van Hove singularities.

Abstract

The out-of-plane hopping in layered metals with strong electronic correlation is analyzed theoretically. By studying the effects of in-plane interactions on the interlayer tunnelling we investigate one of the oldest unresolved problems of high-T$_c$ cuprates, the so-called bilayer splitting. The strong electron-electron interactions within each layer reduce the quasiparticle weight, and modify the hopping between layers. We analyze the effect of the in-plane correlations on the interlayer hopping using a Renormalization Group scheme already applied to the problem of interlayer coherence . The bilayer band splitting acquires a significant temperature and doping dependence, and can be completely suppressed when the Fermi energy coincides with a Van Hove singularity.