Study of the magnetic susceptibility in the spin-Peierls system CuGeO$_3$

TL;DR

This paper uses numerical simulations of a one-dimensional Heisenberg model to analyze the spin-Peierls transition and magnetic properties of CuGeO3, matching experimental observations.

Contribution

It introduces a model including nearest and next nearest neighbor interactions to accurately describe CuGeO3's magnetic behavior.

Findings

Estimated nearest neighbor exchange J ≈ 160 K

Next nearest neighbor exchange ≈ 0.36 J

Successfully reproduces experimental susceptibility and transition temperature

Abstract

We study numerically, using a one-dimensional Heisenberg model, the spin-Peierls transition in the linear Cu$^{2+}$ spin-1/2 chains in the inorganic compound CuGeO$_3$ which has been recently observed experimentally. We suggest that the magnetic susceptibility, the temperature dependence of the spin gap and the spin-Peierls transition temperature of this material can be reasonably described by including nearest and next nearest neighbor antiferromagnetic interactions along the chain. We estimate that the nearest neighbor exchange parameter J is approximately $160\:\rm K$, and that the next nearest neighbor exchange parameter is approximately $0.36\:\rm J$.