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

Tongji University, Shanghai, Shanghai Shi, China
Physics of Condensed Matter (Impact Factor: 1.46). 05/2006; 51(4):473-476. DOI: 10.1140/epjb/e2006-00255-1

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.

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