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Local spin resonance and spin-Peierls-like phase transition in a geometrically frustrated antiferromagnet

S. -H. Lee·C. Broholm·T. H. Kim·W. Ratcliff II·S-W. Cheong
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Abstract

Using inelastic magnetic neutron scattering we have discovered a localized spin resonance at 4.5 meV in the ordered phase of the geometrically frustrated cubic antiferromagnet $\rm ZnCr_2O_4$. The resonance develops abruptly from quantum critical fluctuations upon cooling through a first order transition to a co-planar antiferromagnet at $T_c=12.5(5)$ K. We argue that this transition is a three dimensional analogue of the spin-Peierls transition.

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S. -H. Lee, C. Broholm, T. H. Kim, W. Ratcliff II, S-W. Cheong. 2000-02-07. Local spin resonance and spin-Peierls-like phase transition in a geometrically frustrated antiferromagnet. https://doi.org/10.1103/physrevlett.84.3718

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