Dependence of Band Renormalization Effect on the Number of Copper-oxide Layers in Tl-based Copper-oxide Superconductor using Angle-resolved Photoemission Spectroscopy

TL;DR

This study uses angle-resolved photoemission spectroscopy to compare band renormalization effects in single-layer and multi-layer Tl-based cuprate superconductors, revealing layer-dependent differences that challenge the spin resonance mode hypothesis.

Contribution

First ARPES comparison of nearly optimally-doped multi-layer and single-layer Tl-based cuprates, highlighting layer-dependent band renormalization effects.

Findings

Kink in band dispersion observed in all compounds

Different momentum dependence between single and multi-layer compounds

Layer number influences renormalization effects, suggesting spin resonance mode is unlikely the cause

Abstract

Here we report the first angle-resolved photoemission measurement on nearly optimally-doped multi-layer Tl-based superconducting cuprates (Tl-2212 and Tl-1223) and a comparison study to single layer (Tl-2201) compound. A "kink" in the band dispersion is found in all three compounds but exhibits different momentum dependence for the single layer and multi-layer compounds, reminiscent to that of Bi-based cuprates. This layer number dependent renormalization effect strongly implies that the spin resonance mode is unlikely responsible for the dramatic renormalization effect near the antinodal region.