Freezing of spin dynamics in underdoped cuprates

TL;DR

This paper presents a theoretical framework based on Mori's memory function approach to explain spin dynamics and observed scaling behaviors in underdoped cuprates, aligning with recent neutron scattering experiments.

Contribution

It introduces a model combining temperature-independent spin correlations and damping to account for spin dynamics and central peak phenomena in underdoped cuprates.

Findings

W/T scaling observed in experiments is explained by the model.

The theory accounts for the central peak at low temperatures.

Modified damping functions improve the fit to experimental data.

Abstract

The Mori's memory function approach to spin dynamics in doped antiferromagnetic insulator combined with the assumption of temperature independent static spin correlations and constant collective mode damping leads to w/T scaling in a broad range. The theory involving a nonuniversal scaling parameter is used to analyze recent inelastic neutron scattering results for underdoped cuprates. Adopting modified damping function also the emerging central peak in low-doped cuprates at low temperatures can be explained within the same framework.