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arXiv · 1203.2818

Dynamical lattice instability versus spin liquid state in a frustrated spin chain system

V. Gnezdilov·P. Lemmens·Yu. G. Pashkevich·D. Wulferding·I. V. Morozov·O. S. Volkova·A. Vasiliev
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Abstract

The low-dimensional s=1/2 compound (NO)[Cu(NO3)3] has recently been suggested to follow the Nersesyan-Tsvelik model of coupled spin chains. Such a system shows unbound spinon excitations and a resonating valence bond ground state due spin frustration. Our Raman scattering study demonstrates phonon anomalies as well as the suppression of a broad magnetic scattering continuum for temperatures below a characteristic temperature, T<T*=100K. We interpret these effects as evidence for a dynamical interplay of spin and lattice degrees of freedom that might lead to a further transition into a dimerized or structurally distorted phase at lower temperatures.

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V. Gnezdilov, P. Lemmens, Yu. G. Pashkevich, D. Wulferding, I. V. Morozov, O. S. Volkova, A. Vasiliev. 2012-03-13. Dynamical lattice instability versus spin liquid state in a frustrated spin chain system. https://doi.org/10.1103/physrevb.85.214403

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