Effect of spin excitations on the property of quasiparticles in electron-doped cuprates

TL;DR

This paper proposes that spin fluctuations cause the 50-70 meV dispersion kink in electron-doped cuprates, affecting quasiparticle properties in both superconducting and normal states, aligning with recent experimental observations.

Contribution

It demonstrates that spin excitations are responsible for the dispersion anomaly in electron-doped cuprates, providing a unified explanation across different states and experimental techniques.

Findings

The dispersion kink exists along both nodal and antinodal directions.

The kink appears in both superconducting and normal states.

The density of states shows a hump feature consistent with experiments.

Abstract

It is proposed that the 50-70 meV dispersion anomaly (kink) in electron-doped cuprates revealed by recent angle-resolved photoemission spectroscopy experiments is caused by coupling with the spin fluctuation. We elaborate that the kink exists both along nodal and antinodal directions, and both in the superconducting and normal state. The renormalized effect for the density of states is also studied and the hump feature outside the superconducting coherent peak is established, consistent with recent scanning tunnelling microscopy experiments.