Eur. Phys. J. B 51, 473-476 (2006)
https://doi.org/10.1140/epjb/e2006-00255-1

Second- to first-order transition in two coupled antiferromagnetic rings

Pohl Institute of Solid State Physics, Tongji University, Shanghai, 200092, P.R. China

Corresponding author: ^a 0310103008@smail.tongji.edu.cn

Received: 25 November 2005
Revised: 9 February 2006
Published online: 28 June 2006

Abstract

We numerically investigate an S=1/2 spin model, in which two dimerized antiferromagnetic rings interact with each other ferromagnetically. It is shown that the order of the magnetoelastic transition is strongly affected by the interring coupling J_⊥ and there may exist a critical J_⊥^* dividing the first-order transition and the continuous transition.