Dynamical charge inhomogeneity and crystal-field fluctuations for 4f ions in high-Tc cuprates

TL;DR

This paper investigates how charge inhomogeneity and crystal-field fluctuations in high-Tc cuprates affect the relaxation of 4f ions, proposing a granular model with Wigner crystal-like charge behavior.

Contribution

It introduces a generalized granular model for charge inhomogeneity in cuprates and links it to crystal-field relaxation mechanisms in rare-earth ions.

Findings

Charge inhomogeneity influences crystal-field relaxation.

Granular model describes charge subsystem as a Wigner crystal.

Relaxation mechanism aligns with magnetoelastic theories.

Abstract

The main relaxation mechanism of crystal-field excitations in rare-earth ions in cuprates is believed to be provided by the fluctuations of crystalline electric field induced by a dynamic charge inhomogeneity generic for the doped cuprates. We address the generalized granular model as one of the model scenario for such an ingomogeneity where the cuprate charge subsystem remind that of Wigner crystal with the melting transition and phonon-like positional excitation modes. Formal description of R-ion relaxation coincides with that of recently suggested magnetoelastic mechanism.