Dynamical properties of the compounds CuGeO_3 and \alpha'--NaV_2O_5 at temperatures $T\neq 0$

TL;DR

This paper investigates the finite-temperature dynamical properties of frustrated spin-1/2 Heisenberg chains, identifying spectral features like the spinon continuum boundary and proposing a method to determine coupling constants, with comparisons to experimental data.

Contribution

It introduces a simple spectral analysis method to extract nearest neighbor coupling J from dynamical structure factors at finite temperatures.

Findings

Identified a sharp upper boundary of the spinon continuum.

Proposed a method to determine J from spectral width.

Compared theoretical results with neutron scattering data.

Abstract

The dynamical structure factor of the frustrated spin 1/2 Heisenberg model for a series of frustration parameters at finite temperatures is presented. A sharp upper boundary of the spinon continuum is found. A simple method to extract the nearest neighbour coupling J from the spectral width is suggested. Signatures of frustration are discussed and a comparison with neutron inelastic scattering data is given.